||This article may contain excessive, poor, or irrelevant examples. (March 2010)|
In mathematics 
Forty-seven is the fifteenth prime number, a safe prime, the thirteenth supersingular prime, and the sixth Lucas prime. Forty-seven is a highly cototient number. It is an Eisenstein prime with no imaginary part and real part of the form .
Forty-seven is a strictly non-palindromic number.
Forty-seven is a Carol number.
In science 
- Messier object M47, a magnitude 4.5 open cluster in the constellation Puppis
- The New General Catalogue object NGC 47, a barred spiral galaxy in the constellation Cetus. This object is also designated as NGC 58.
- The Saros number of the solar eclipse series which began in April 1306 BC and ended in May 26 BC. The duration of Saros series 47 was 1280.1 years, and it contained 72 solar eclipses.
- The Saros number of the lunar eclipse series which began in July 1275 BC and ended in February AD 258. The duration of Saros series 47 was 1537.5 years, and it contained 86 lunar eclipses.
As an in-joke 
Forty-seven has been the favorite number of Pomona College, California, USA, since 1964. A mathematical proof, written in 1964 by Professor Donald Bentley, supposedly demonstrates that all numbers are equal to 47. However, Bentley offered it as a "joke proof" to further a popular student research project that listed real and imaginative "47 sightings". Bentley used the invalid proof to introduce his students to the concept of mathematical proofs. The proof used limits to show that the sum of the two equal sides of an isosceles triangle is equal to the base side. Bentley chose forty-seven as the base side, but he could have used any number.
Joe Menosky graduated from Pomona College in 1979 and went on to become one of the story writers of Star Trek: The Next Generation. Menosky "infected" other Star Trek writers with an enthusiasm for the number 47. As a result, 47, its reverse 74, its multiples, or combinations of 47 occur surreptitiously in almost every episode of the program and its spin-offs Star Trek: Deep Space Nine, Star Trek: Voyager and Star Trek: Enterprise. Forty-seven might be mentioned in dialogue or appear on a computer screen, for example:
- In Star Trek: Generations, Scotty manages to beam up only 47 El-Aurians before their ship is destroyed by the energy ribbon.
- In the TNG episode "Darmok", the computer of the Enterprise reports to have found 47 occurrences of the word "Darmok" in its database.
- In the DS9 episode "Whispers", the planet Parada 4 has seven moons.
- In the Voyager episode "Parallax", we learn that the Emergency Medical Holographic Channel is 47 and that the EMH has the experience of 47 individual medical officers.
- In the Voyager episode "Non Sequitur", Harry Kim lives in apartment 4-G, G being the seventh letter of the alphabet. The intentionality of this reference to 47 was confirmed by Brannon Braga, the writer of that episode.
- In the Voyager episode "Before And After", the phase shift is 1.47
- In the 2009 film Star Trek, the Enterprise was built in Sector 47 of the Riverside Shipyards, and 47 Klingon ships are said to have been destroyed by Nero's ship, the Narada.
J. J. Abrams, who produced and directed the Star Trek film, carried a few references to the Star Trek franchise into contemporary episodes of his TV series, Fringe, one of those references being the number 47. In the Season 1 episode "Bad Dreams", aired shortly before the release of Star Trek in theaters, Nick Lane's bulletin board features a large centrally-located sheet of paper with only the number 47 in huge typeface. It recurs again in the series, for example 47 minutes being the maximum amount of time for a time chamber in the show to last, and there being exactly 47 shapeshifters. J.J. Abrams continues to incorporate 47 into movies and shows he produces and directs. There are many 47's in Fringe, Alias, and recently in Revolution, which Abrams is a producer. In the Season 1 episode "Soul Train" of the show Revolution, the characters are involved with an old train engine where the engine number happens to be 47.
In pop culture 
The 47 society is an outgrowth of the "movement" started at Pomona College. They explore the belief that 47 occurs in nature more frequently than other numbers and share their personal sightings in consideration of 47 being "the quintessential random number".
In the 1976 horror film The Omen, photographer Keith Jennings shows Ambassador Thorn that there are 47 crosses nailed to the door of Father Brennan's accommodation, in an attempt to keep Satanic forces from entering. This reference also occurs in David Seltzer's novelization of the film, although the same priest is named Father Tassone.[importance?]
In the 2001 TV series Alias, the number 47 bears a specific significance concerning the Milo Rambaldi mythology. Among other things, page 47 of the Rambaldi manuscript contains the prophecy regarding the Chosen one and the Passenger. The number also often appears in different places through the series, for example in keycodes, safe-deposit boxes, hotel rooms or the number of victims in different attacks or accidents. It also appears as the same way in the 2008 TV series Fringe, which has the same creator as Alias..[importance?]
In the TV series Castle, the number 47 is featured numerous times, and ranges in mentions from number on a door, the year (1947), to the amount of seconds the intro to the show lasts. The most notable however is the episode "47 Seconds" in which Castle and Beckett recreate the 47 seconds previous to a bomb exploding..[importance?]
The number 47 also appears in music. 47 is the number of miles of barbed wire walked by the singer of Bo Diddley's "Who Do You Love". In 1998, Japanese electronic musician Takako Minekawa released the album Cloudy Cloud Calculator, which featured a song about the number 47 entitled "Kangaroo Pocket Calculator". The song repeats, "47 is a magical number. 47 plus 2 equals 49. 47 times 2 equals 94. 49 and 94. 94 and 49. Relationship between 47 and 2… is magic" and eventually concludes, "Isn't it a coincidence?" Leslie Sarony published his song "Forty-Seven Ginger-Headed Sailors" in 1928. Forty-seven is the usual number strings of a pedal harp. 47 is a song by Sunny Day Real Estate. Object 47 (named as the 47th release in the discography) is the name of an album release from Wire.
In National Treasure: Book of Secrets, the President asks Ben Gates to let him know what is on "page 47" of "the presidents book of secrets", which contains the national secrets of the U.S. presidents.
47 appears on the top of the police van in the Nicolas Cage film, Snake Eyes.
In J.J. Abrams' SUPER 8, one of the characters, "Charles" is trying to create and enter a film. Part of the film takes place in "warehouse 47"
47 is the total numbers of balloons that a player can collect in Rareware's Nintendo 64 game Diddy Kong Racing.
The Wild, Wild West is a song by The Escape Club from their similarly named debut album, Wild Wild West that begins with the verse "Forty seven dead beats living in the back street/north east west south all in the same house/sitting in a back room waiting for the big boom/I'm in a bedroom waiting for my baby".
In the 2011 American spy film Mission: Impossible – Ghost Protocol produced by J.J. Abrams, train car #47 is the team's safehouse. At the end of the movie the team also meets up at Pier 47 in Seattle, WA.
Other appearances 
Forty-seven is the number of Ray Garraty, the main character in The Long Walk by Stephen King. In the animated web series Afterworld, the worldwide EMP re-occurs every 47 minutes. The number 47 appears on every bottle produced by Full Sail Brewery of Hood River, Oregon. This was representative of the number of employees at one time, and CEO Irene Firmat was apparently amused that it was 47, supposedly the most common random number. The brewery now has more employees, but the number remains on the bottles. In the Japanese Anime "Claymore", the main character, Clare, is the 47th claymore. The main character of Hitman (video game series) is named as Agent 47.
Calendar years 
- Telephone dialing country code for Norway
- The AK-47, also known as a Kalashnikov rifle, is one of the most widely-used military weapons in the world.
- The CH-47 Chinook, a helicopter.
- 47 is the number of the French department Lot-et-Garonne
- The Tropic of Cancer and the Tropic of Capricorn are located 47 degrees apart.
- The P-47 Thunderbolt was a fighter plane in WWII
- Agent 47 is the name given to the main character in the game Hitman
- The NGC / IC Project - Home of the Historically Corrected New General Catalogue (HCNGC) since 1993
- Internet Archive Wayback Machine
- NASA - Lunar Eclipses of Saros Series 1 to 175
- "The Mystique of 47". Pomona College (via Internet Archive). Archived from the original on 2006-09-01. Retrieved 2010-05-16.
- "The Mystery of 47". Pomona College. Retrieved 2007-08-29.
- "Stardate 47". Pomona College (via Internet Archive). Retrieved 2010-05-17.
- "Starbase Pomona". Pomona College (via Internet Archive). Retrieved 2010-05-17.
- schlock.net: A letter from Brannon Braga
- Roco. "Revolution Observations: 1.05 Soul Train". Seriable.com. Retrieved 28 April 2013.
- The 47 Society
- Digital Collections - Music - Sarony, Leslie. The Church song "Destination" has a lyric, "Page forty-seven is unsigned, I need it by this evening." Forty-seven ginger-headed sailors [music]
- - Escape Club - Wild Wild West lyrics by alllyrics.com
- "Six easter eggs you may or may not have noticed in Mission: Impossible – Ghost Protocol". ViralInfection.com, December 22, 2011.
- MovieMaps.org - Mission: Impossible - Ghost Protocol - Pier 47
- Oregon Business Magazine, October 2008
|Wikimedia Commons has media related to: 47 (number)|
- Frequently Asked Questions about 47 and The 47 Society
- Pomona College's Star Trek Connection
- Star Trek Voyager and the Number 47 - Featurette, an impressive video montage, very thorough
- 47 in the Alias fandom (from the All Alias Guide)