14 (number)

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← 13 14 15 →
Cardinalfourteen
Ordinalth
Numeral systemtetradecimal
Factorization
Divisors1, 2, 7, 14
Greek numeralΙΔ´
Roman numeralXIV
Binary11102
Ternary1123
Senary226
Octal168
Duodecimal1212
HexadecimalE16

14 (fourteen) is the natural number following 13 and preceding 15.

In mathematics

Fourteen is a composite number, its proper divisors being 1, 2, 7 and 14.

14 is the 3rd discrete biprime ( 2 . 7 ) and the 3rd member of the (2.q) discrete biprime family. The number following 14;15,is itself a discrete biprime and this is the first such pair of discrete biprimes The next example is the pair commencing 21

The aliquot sum σ(n) of 14 is 10, also a discrete biprime and this is again the first example of a discrete biprime having an aliquot sum in the same form. 14 has an aliquot sequence of 6 members ( 14,10,8,7,1,0) 14 is the third composite number in the 7-aliquot tree.

Fourteen is itself the Aliquot sum of two numbers; the discrete biprime 22, and the square number 169.

It is the base of the tetradecimal notation.

In base fifteen and higher bases (such as hexadecimal), fourteen is represented as E.

Fourteen is the sum of the first three squares, which makes it a square pyramidal number.

This number is the lowest even n for which the equation φ(x) = n has no solution, making it the first even nontotient (see Euler's totient function).

14 is a Catalan number, the only semiprime among all Catalan numbers.

Take a set of real numbers and apply the closure and complement operations to it in any possible sequence. At most 14 distinct sets can be generated in this way. This holds even if the reals are replaced by a more general topological space. See Kuratowski's closure-complement problem.

Fourteen is a Keith number in base 10: 1, 4, 5, 9, 14, 23, 37, 60, 97, 157...

Fourteen is an open meandric number.

Fourteen is a Companion Pell number.

According to the Shapiro inequality 14 is the least number n such that there exist such that

where .

There are fourteen possible Bravais lattices that fill three-dimensional space.

The cuboctahedron, the truncated cube, and the truncated octahedron each have fourteen faces. The rhombic dodecahedron, which tessellates 3-dimensional space and is the dual of the cuboctahedron, has fourteen vertices. The truncated octahedron, which also tessellates 3-dimensional space, is the only permutohedron.

In science

Chemistry

Astronomy

  • The Saros number of the lunar eclipse series which began on June 1, 2230 B.C. and ended on July 19, 932 B.C. The duration of Saros series 14 was 1298.1 years, and it contained 73 lunar eclipses.

In religion

As lucky or unlucky number

  • 14 is a lucky number to the modern Mandarin-speaking Chinese society. 14 is said as "shi si," which sounds like "more/deep thinking", 14 as musical pronounce sound is "dou fa," which exactly sounds like "all have fortunes"
  • 14 is an unlucky number to the Chinese. 14, when it literally means "fourteen", is usually said in Mandarin as "shi si," which sounds like "ten die". Also, a common way to say "one" in Mandarin is as "yao". Therefore, 14 can also be said in Mandarin as "yao si," literally "one four," but it sounds like "want to die," which also has an unlucky connotation. In Cantonese, fourteen is said as "sap say", which sound like "sat say", meaning "sure death". See Numbers in Chinese culture

Age 14

  • In the UK a minor aged 14 can be tried in court for any sexual offense.
  • This is the youngest age a person could watch a TV-14 rated show without consent from a legal guardian.
  • In some U.S. states, you can obtain a driving (learner's) permit at 14 with parental consent.
  • Age 14 is the earliest that the emancipation of children can occur in the U.S.
  • Minimum age a person can purchase, rent or buy tickets to a 14A rated movie in Canada without an adult. Rating are provincial, so ratings may vary. A movie can be 14A in one or some provinces and PG in other provinces. A movie can also be rated 14A in one or some provinces and 18A in other provinces. Quebec has a different rating system for films.
  • Youngest age in Canada a person can watch a 14+ rated show without consent from a legal guardian.
  • Minimum age at which one can view, rent, purchase, or buy tickets to an 18A rated movie which an accompanying adult in the Canadian provinces of the Maritimes and Manitoba.
  • Minimum age at which one can work in many U.S states. Some require parental consent while others don't.

In sports

Neo-Nazi symbol

Among White Nationalists, 14 signifies the "Fourteen Words"—"We must secure the existence of our people and a future for white children"—attributed to David Lane. Often found in combination with 88 (1488, 8814, 14/88, etc.).

In other fields

Fourteen is:

File:14-bis-wth-air-ballon-aid.jpg
Santos Dumont's 14-bis hanging from Airship 14.
  • The Number 14 airship by Alberto Santos Dumont that was used to test the aerodynamics of his 14-bis airplane, the first one to fly practically (depending on the definition of "flying practically").
  • The number of letters in the Law of Thelema, "Do what thou wilt."
  • An alternate name for the small American community of Ranger, West Virginia
  • The number of the French department Calvados

Historical years

14 A.D., 14 B.C., 1914, 2014, etc.

References