Number 47 is commonly found in mathematics, science, history, technology, politics, religion and many other places. Click on the arrows to expand.
Mathematics
Euclid’s 47th Proposition
The 47th proposition in Euclid’s Elements, also known as Proposition 47 of Book I, is one of the most famous theorems in mathematics:
Euclid’s 47th Proposition (Book I)
“In right-angled triangles, the square on the side opposite the right angle (the hypotenuse) is equal to the sum of the squares on the sides containing the right angle.”
This is more commonly known today as the Pythagorean Theorem.
47 Prime Number
A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. Since 47 has only two divisors, 1 and 47, it is considered a prime number.
47 is a Supersingular Prime
A supersingular prime is a specific type of prime number that appears in various areas of mathematics, particularly in number theory and group theory.
There are exactly 15 supersingular primes:
- 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 47, 59, and 71.
47 is indeed a supersingular prime.
47 is a highly cotoitent number
47 is reported as a likely highly cototient number based on an informal check.
Highly cototient numbers are those that have an unusually high number of divisors compared to their size. There is no formal definition of a highly cototient number, but they are interesting for their mathematical properties.
The code I used implements a simplified check for high cototiency by looking for solutions to the equation x – φ(x) = k for small values of k, where φ(x) is Euler’s totient function (the number of positive integers less than x that are relatively prime to x).
47 Safe Prime
A safe prime is a prime number of the form 2q + 1, where q is also a prime number.
In the case of 47:
- We can express it as 2 * 23 + 1.
- 23 is also a prime number.
Therefore, 47 fulfills the criteria of a safe prime.
47 Eisenstein Prime
47 is indeed an Eisenstein prime.
An Eisenstein prime is a specific type of prime number within the complex number system. It’s defined in relation to Eisenstein integers, which are complex numbers of the form a + bω, where a and b are integers and ω is a complex cube root of unity.
Eisenstein primes congruent to 2 (mod 3): These are the ordinary primes that are congruent to 2 modulo 3. 47 fits this category.
47 is a Lucas Prime
A Lucas prime is a Lucas number that is also a prime number.
Lucas numbers are a sequence of numbers similar to Fibonacci numbers, but with different starting values.
- The first few Lucas numbers are: 2, 1, 3, 4, 7, 11, 18, 29, 47, …
As you can see, 47 is indeed a Lucas number and it’s also a prime number, making it a Lucas prime.
47 Keith Number
47 is indeed a Keith number.
A Keith number is a number whose digits form a sequence that eventually includes the original number.
For example, with 47:
- The digits are 4 and 7.
- We form a sequence: 4, 7, 11, 18, 29, 47.
- As you can see, 47 appears in the sequence, making it a Keith number.
It’s an interesting property of numbers!
47 Carol Number
47 is a Carol Number
A Carol number is a natural number c such that c = p · 2^p − 1 for some prime p.
For 47:
47 = 2 * (2^2 – 1) = 2 * 3 = 6.
We need to find a prime p such that 47 = p * (2^p – 1).
By trial and error, we find that p = 2 satisfies the equation:
47 is a highly cotoitent number
47 is reported as a likely highly cototient number based on an informal check.
Highly cototient numbers are those that have an unusually high number of divisors compared to their size. There is no formal definition of a highly cototient number, but they are interesting for their mathematical properties.
The code I used implements a simplified check for high cototiency by looking for solutions to the equation x – φ(x) = k for small values of k, where φ(x) is Euler’s totient function (the number of positive integers less than x that are relatively prime to x).
47 is quintessential random number
The number 47 has unexpectedly garnered a reputation as the “quintessential random number”. This peculiar claim originated from a rather playful observation. Some people noticed the number 47 appearing more frequently in various contexts than other two-digit numbers.
Science
19.47 Degrees
19.47 degrees is the angle at which the waves created by moving objects in water, such as ships or ducks, are formed in relation to the direction of motion. This angle is known as Kelvin’s angle, and is a characteristic of the Kelvin wake pattern. The angle is maintained regardless of how fast the object is moving.
The angle of 19.47 degrees is significant because it marks the point where a tetrahedron intersects a sphere, dividing it into a two-thirds to one-third ratio. This geometric relationship, along with the concept of tetrahedra surrounding spheres, has been proposed by some to represent the structure of spacetime at the Planck scale, according to Nassim Haramein. The 19.47-degree latitude is also seen by some as a statistically significant point on Earth, with landmarks and phenomena like volcanoes, Jupiter’s Red Spot, and regions on Mars being located near this latitude.
Silver’s atomic number is 47.
Silver (Atomic Number 47) is a shiny, white metallic element with the chemical symbol Ag, derived from the Latin word argentum. It is a precious metal known for its high electrical and thermal conductivity, as well as its malleability and lustrous appearance. Silver has been used for thousands of years in jewelry, coins, utensils, and industrial applications, including electronics and solar panels. It occurs naturally in the Earth’s crust and is often found in ores alongside lead, zinc, and copper. Its long-standing value and beauty have made it both a cultural symbol of wealth and a practical material in modern technology.
Messier M47
Messier 47 (M47) is a bright open star cluster located about 1,600 light-years away in the constellation Puppis. It contains around 50 visible stars, primarily young, hot blue stars, and is estimated to be about 78 million years old. With an apparent magnitude of 4.4, it can be seen with the naked eye under dark skies and is an easy target for binoculars or small telescopes. Discovered by Giovanni Hodierna before 1654 and cataloged by Charles Messier in 1771, M47 is notable for its brightness and proximity to the similar, but older, cluster Messier 46.
NGC 47
NGC 47 is a spiral galaxy located in the constellation Cetus, approximately 236 million light-years from Earth. It has a magnitude of around 13, making it a faint object visible only through larger telescopes. NGC 47 features loosely wound spiral arms and is classified as a SB(rs)bc type galaxy, indicating a barred spiral structure with some ring-like features. It was discovered in 1886 by Ernst Wilhelm Leberecht Tempel. NGC 47 is sometimes confused with NGC 58, as early cataloging led to duplicate entries for the same object.
47 Tucanae
47 Tucanae (also known as NGC 104) is a globular star cluster located in the constellation Tucana, about 13,000 light-years from Earth. It is the second-brightest globular cluster in the night sky (after Omega Centauri) and one of the most massive, containing millions of stars packed tightly together. With an apparent magnitude of 4.0, it is visible to the naked eye from the Southern Hemisphere. 47 Tucanae is notable for its dense core, ancient stars, and the presence of many millisecond pulsars and X-ray binaries, making it a key object of study in stellar evolution and dynamics.
Mars 47 Year Cycle
The Mars 47-year cycle refers to a long-term pattern in the orbital relationship between Mars and Earth, where the positions of Mars in the sky repeat closely every 47 years. This cycle is based on the periodic alignment of Mars’ oppositions—when Mars is directly opposite the Sun in the sky as seen from Earth.
Every 15 to 17 years, Mars experiences a perihelic opposition, when it is both opposite the Sun and closest to Earth in its orbit, making it appear especially bright. After about 47 years, the timing and position of these perihelic oppositions repeat in a very similar way due to the synodic and orbital rhythms of Earth and Mars.
This cycle is useful for astronomers and mission planners, especially when scheduling Mars missions, as it helps identify optimal launch windows with shorter travel times and lower energy costs.
47 Chromosomes
47 Chromosomes is a condition known as trisomy. It occurs when a person has an extra chromosome in each of their cells. The most common type of trisomy is Down syndrome, where an extra chromosome is present on chromosome 21.
Other types of trisomy include:
Patau syndrome: An extra chromosome on chromosome 13
Edwards syndrome: An extra chromosome on chromosome 18
Religion
40 Days of Lent
The 40 Days of Lent is the solemn Christian religious observance in the liturgical year commemorating the 40 days Jesus spent fasting in the desert and enduring temptation by Satan, according to the Gospels of Matthew, Mark and Luke, before beginning his public ministry.
If you count the days between Ash Wednesday to Easter Sunday it is 47 days not 40. The reason being that Sundays are not included in the count.
Jesus Crucifixion
April 7th of AD 30 and April 3rd AD 33.
are the dates that has been calculated by some scholars, using astronomical data, as a possible date of the crucifixion.
47th Pope
Pope Simplicius was the 47th Pope. He reigned from 468 to his death in 483. He was the 47th Pope during the decade of 470’s AD. He lived during a time of great political and social upheaval, with the Western Roman Empire collapsing in 476.
History
4th of July
July 4th, also known as Independence Day, is a significant federal holiday in the United States. It commemorates the adoption of the Declaration of Independence on July 4, 1776, when the thirteen American colonies declared their independence from Great Britain.
On January 10, 1776, a 47 page pamphlet named “Common Sense” was published by Thomas Paine advocating independence from Great Britain to people in the Thirteen Colonies. This pamphlet helped inspired the Declaration of Independence and the American Revolution.
Thomas Jefferson
Thomas Jefferson born on April 13, 1743, was an American statesman, planter, diplomat, lawyer, architect, philosopher, and Founding Father who served as the third president of the United States from 1801 to 1809. He was the primary author of the Declaration of Independence. Thomas Jefferson died on July 4, 1826 exactly 50 years after the signing of the Declaration of Independence.
The Gettysburg Address
The Gettysburg Address was a speech given by Abraham Lincoln on November 19, 1863 which began by saying “Four score and seven years ago”. It refers to the 87 years that had passed since the Continental Congress adopted the Declaration of Independence on July 4, 1776. “Score” is an old-fashioned term that means 20 years, so “four score and seven” is another way of saying 87 years.
Alexander Graham Bell
Alexander Graham Bell born on March 3, 1847, was Scottish-born Canadian-American inventor, scientist and engineer who is credited with patenting the first practical telephone. He also co-founded the American Telephone and Telegraph Company (AT&T) in 1885. Using his sound skills, he created the telephone and made the first call in 1876. He called Thomas Watson, his assistant, and said, “Mr. Watson, come here. I want to see you.” Graham’s inventions have allowed for communication to continue to expand.
Thomas Edison
Thomas Edison, born on February 11, 1847, was an American inventor and businessman. He is regarded as the most prolific inventor in American history. He developed many devices in fields such as electric power generation, mass communication, sound recording, and motion pictures. These inventions, which include the phonograph, the motion picture camera, and early versions of the electric light bulb, have had a widespread impact on the modern industrialized world.
Henry Ford
Henry Ford was an American industrialist and business magnate. As the founder of the Ford Motor Company he is credited as a pioneer in making automobiles affordable for middle-class Americans. Ford was a conspiracy theorist who drew on a long tradition of false allegations against Jews. Ford claimed that Jewish internationalism posed a threat to traditional American values, which he deeply believed were at risk in the modern world. Henry Ford died on April 7, 1947
The Paris Peace Treaties
The Paris Peace Treaties, signed in February 1947, marked the formal end of World War II for several Axis powers. 1 These treaties were negotiated among the Allied powers (primarily the United States, the Soviet Union, the United Kingdom, and France) and five former Axis states: Italy, Romania, Hungary, Bulgaria, and Finland.
1947 Roswell Incident
The Roswell Incident is one of the most famous UFO cases in history. It occurred on July 8, 1947 in Roswell, New Mexico (the 47th State).
Pop Culture
47′ Clothing Brand
‘47 is an American lifestyle brand that brings together sports, fashion, and cultural influences. It offers a wide range of licensed headwear, apparel and gear tailored for men, women, and children.
Agent 47
Agent 47, the protagonist of the Hitman video game franchise, is a genetically engineered assassin, known for his skill and efficiency, and was formerly an agent of the International Contract Agency (ICA)
47 Ronin
The 47 Ronin is a true Japanese story about 47 masterless samurai (ronin) who avenged their wrongfully killed lord. They patiently planned and executed their revenge, then turned themselves in and were ordered to commit ritual suicide. The tale is a symbol of loyalty, honor, and sacrifice.
47 Meters Down
Sisters Lisa and Kate are vacationing in Mexico when they decide to go on a once-in-a-lifetime adventure: cage diving with great white sharks. But their thrill quickly turns into a nightmare when the winch holding their cage breaks, sending them plummeting 47 meters down to the ocean floor. Trapped in the deep, low on oxygen, and surrounded by deadly sharks, the sisters must fight against time, terror, and the crushing pressure of the deep sea to survive.
47 by Walter Mosley
47 is a young slave boy living under the watchful eye of a brutal slave master. His life seems doomed until he meets a mysterious runaway slave, Tall John. 47 finds himself swept up in a struggle for his own liberation.
Places
President Donald J. Trump Avenue Hialeah, Florida
The 47th President of the United States, Donald J. Trump has a avenue in Hialeah named in his honor. Palm Avenue is also 47th Avenue in Miami-Dade County.
Palm Beach 47th County in Florida
The Florida Legislature established Palm Beach County on July 1, 1909, and it became Florida’s 47th county.
The 47th President of the United States, Donald J. Trump resides is in Mar-a-Lago located at 1100 S Ocean Blvd, Palm Beach, FL 33480, USA.
One of the zip codes in Palm Beach County is 33407.
New Mexico 47th State
New Mexico is a US state known for its diverse landscapes, rich Native American, Spanish, and Mexican history, and vibrant arts scene. Its capital is Santa Fe, and it became the 47th state in 1912.
Roswell, New Mexico is the place surrounding the crash and recovery of a U.S. Army Air Forces high-altitude balloon in 1947. Initially, the military claimed it was a “flying disc,” but later stated it was a weather balloon. This event became the center of many UFO conspiracy theories.
The Loretto Chapel is a historic chapel in Santa Fe, New Mexico, famous for its “Miraculous Staircase.” This freestanding spiral staircase, built in 1876, has no visible central support, and its construction remains a mystery.
47th Street in Times Square
47th Street in NYC is a bustling and iconic stretch known primarily for its Diamond District. 47th street intersects with the area of Times Square which is formed by the junction of Broadway and Seventh Avenue, and extends roughly from 42nd Street to 47th Street.
There are 47 Prefectures of Japan.
Japan’s administrative division is structured into 47 prefectures. These 47 prefectures showcase a wide range of geographical landscapes, cultural nuances, and climatic conditions. This contributes to the diverse experiences one can have while traveling throughout Japan.
*347 FHP: A Lifeline on Florida Roads
“347 FHP“ is a quick and easy way to contact the Florida Highway Patrol (FHP) and Florida Department of Transportation (FDOT) Road Rangers from your mobile phone. They are like Angels of the road that while help you stay safe in dangerous situation on Florida Highways.
(305) 471-8477(TIPS) Tips Hotline Miami-Dade
Crime Stoppers of Miami-Dade and The Florida Keys is a community-based organization which gives residents the opportunity to become involved in the fight against crime in Miami-Dade County and The Florida Keys. The tip must come through the Crime Stoppers anonymous tip lines, 305 471-8477, online at CrimeStoppers305.com or via the mobile website.
Aviation & Technology
Aviation and its connections with number 47.
Boeing 747 -The Queen of the Skies
The historic 747, dubbed the ‘Queen of the Skies,’ revolutionized air travel as the world’s first twin-aisle airplane and enabled more people to fly farther, faster and more affordably than ever before. Marked by its distinctively recognizable hump, this iconic airplane is a symbol of great engineering, innovation and often noted as an outstanding work of architecture. Since production began in 1967, and the first 747-100 completed is first test flight in 1969, more than 100 customers have purchased 1,574 aircraft, logging more than 118 million flight hours and nearly 23 million flight cycles. The 747 wide-body jet, with its signature upper deck “hump”, is one of the most recognizable aircraft in the world.
Boeing 247 -World’s First Modern Airliner
The world’s first modern airliner, the Boeing 247 revolutionized air transportation when it entered service with United Air Lines in 1933. With its sleek, low-wing, all-metal construction; retractable landing gear; and supercharged, air-cooled engines, the Boeing 247 was 50 percent faster than its competitors.
Bell 407 Helicopter
The Bell 407 is a four-blade, single-engine, civil utility helicopter. A derivative of the Bell 206L-4 LongRanger, the 407 uses the four-blade, soft-in-plane design rotor with composite hub developed for the United States Army’s OH-58D Kiowa Warrior instead of the two-blade, semi-rigid, teetering rotor of the 206L-4.
N-47 -FAA Bombardier Global 5000
N-47 is an experimental Bombardier Global 5000 aircraft owned by the FAA ( Federal Aviation Administration) and used to for testing systems such as NextGEN.
14 CFR Part 47 -AIRCRAFT REGISTRATION
14 CFR Part 47 prescribes the requirements for registering aircraft under 49 U.S.C. 44101-44104. Subpart B applies to each applicant for, and holder of, a Certificate of Aircraft Registration, AC Form8050-3. Subpart C applies to each applicant for, and holder of, a Dealer’s Aircraft Registration Certificate, AC Form 8050-6.
14 CFR Part 147 -AVIATION MAINTENANCE TECHNICIAN SCHOOLS
14 CFR Part 147 prescribes the requirements for issuing aviation maintenance technician school certificates and associated ratings and the general operating rules for the holders of those certificates and ratings.
Military
F-47
The F-47 is Boeing’s upcoming sixth-generation fighter jet for the US Air Force. It’s designed with advanced stealth, long-range capabilities, and sensor technology, and will work with drones. It’s meant to replace the F-22 and counter future threats.
X-47
The Northrop Grumman X-47 is a demonstration unmanned combat aerial vehicle. The X-47 began as part of DARPA’s J-UCAS program, and is now part of the United States Navy’s UCAS-D program to create a carrier-based unmanned aircraft.
B-47 Stratojet
The B-47 was a pioneering American jet bomber during the Cold War, known for its swept wings and six engines. It played a key role in U.S. strategic air power. Its engine pod design had a significant and lasting impact on modern aircraft design, particularly in the development of jet airliners.
CH-47 -Chinook
The Boeing CH-47 Chinook is a tandem-rotor helicopter originally developed by American rotorcraft company Vertol and now manufactured by Boeing Defense, Space & Security. The Chinook is a heavy-lift helicopter that is among the heaviest lifting Western helicopters. The CH-47D Chinook is the U.S. Army’s primary heavy troop and supply transport aircraft. Originally fielded in the Vietnam War, the CH-47 has undergone a series up upgrades to increase lift and airworthiness in combat environments.
Beginning in 1982 and ending in 1994, all CH-47A, B and C models were upgraded to the CH-47D version, which remains the U.S. Army standard and features composite rotor blades, an improved electrical system, modularized hydraulics, triple cargo hooks, avionics and communication improvements, and more powerful engines that can handle a 19,500 lb load – nearly twice the Chinook’s original lift capacity. An upgrade program exists to remanufacture 300 of the current fleet of 425 CH-47D’s to the CH-47F standard. The MH-47E is the Special Forces variant of the Chinook and will be remanufactured to the MH-47G.
P-47 -Thunderbolt
The Republic P-47 Thunderbolt is a World War II-era fighter aircraft produced by the American company Republic Aviation from 1941 through 1945. It was a successful high-altitude fighter, and it also served as the foremost American fighter-bomber in the ground-attack role. The P-47 proved to be one of the best performing fighters to see combat. Thunderbolts were lost at the exceptionally low rate of 0.7 per cent per mission and Jug pilots achieved an aerial kill ratio of 4.6:1. In the European Theater, P-47 pilots destroyed more than 7,000 enemy aircraft, more than half of them in air-to-air combat.
C-47 -Skytrain
Few aircraft are as well known, were so widely used or used as long as the C-47. Affectionately nicknamed the “Gooney Bird,” this aircraft was adapted from the Douglas DC-3 commercial airliner. The U.S. Army Air Corps ordered its first C-47s in 1940, and by the end of World War II, procured a total of 9,348. These C-47s carried personnel and cargo around the globe. They also towed troop-carrying gliders, dropped paratroops into enemy territory, and air evacuated sick or wounded patients. A C-47 could carry 28 passengers, 18-22 fully equipped paratroopers, about 6,000 lbs. of cargo or 18 stretchers and three medical personnel. More than 16,000 DC-3s and military version C-47s were built in 50-plus variants. More than 300 are still flying today.
M47 Patton Tank
The M47 Patton was an American Medium tank, a development of the M46 Patton mounting an updated turret, and was in turn further developed as the M48 Patton. It was the second American tank to be named after General George S. Patton, commander of the U.S.
AK-47
The AK-47 (Avtomat Kalashnikova 1947) is one of the most iconic and widely used assault rifles in the world, developed by Mikhail Kalashnikov in the Soviet Union.
Sukhoi Su-47
The Sukhoi Su-47 “Berkut” (meaning “Golden Eagle”) was a Russian experimental jet fighter developed by Sukhoi in the 1990s.
Sports
Don Shula: The Winningest Coach in NFL History
Don Shula is a legendary figure in the NFL, renowned for his exceptional coaching career. He holds the record for the most wins by an NFL head coach, with a total of 347 victories. His 1972 Dolphins team is famous for achieving a perfect 17-0 regular season, a feat unmatched in NFL history.
Hard Rock Stadium
It is located at 347 Don Shula Dr Suite 102, Miami Gardens, FL 33056, USA. The stadium is exit 47 off the Florida Turnpike.
Michael Irvin UM #47
Michael Irvin #47 was a standout wide receiver at the University of Miami. He played for the Hurricanes from 1985 to 1987 and was a key contributor to their success during that time.
Here are some of his notable accomplishments at UM:
National Championship: He was a member of the 1987 Miami Hurricanes team that won the national championship.
All-American: Irvin was named a consensus All-American in 1987.
Movies, Games & Books
Iron Man
In the movie Iron Man, Tony Stark father held the Stark Expo in 1974. In Iron Man 2 War during the final fight scene War Machine suddenly has AF-47 on his left shoulder.
Seabiscuit
Seabiscuit was a famous American thoroughbred racehorse who became a symbol of hope and resilience during the Great Depression. Seabiscuit’s story is one of an underdog who rose to become a national hero, providing a much-needed boost of morale during a difficult time in American history.
The story of Seabiscuit was adapted into a popular and critically acclaimed film. The film is based on the bestselling book “Seabiscuit: An American Legend” by Laura Hillenbrand. The film was a critical and commercial success, earning praise for its performances, storytelling, and historical accuracy. The “Seabiscuit” movie is a powerful portrayal of a true American story that resonated with audiences.
Seabiscuit passed away from a heart attack at the age of 14 on May 17, 1947
47 Ronin
The 47 Ronin is a legendary tale from Japanese history and samurai culture, symbolizing loyalty, honor, and the bushidō code.
The 2013 “47 Ronin” movie is a fantasy action film starring Keanu Reeves. It’s a loose adaptation of the classic Japanese legend, adding mythical creatures and magic to the historical story of samurai seeking revenge.
