(15, XV) is the natural number
and preceding sixteen
. Fifteen is a triangular number
. It is a composite number
; its proper divisors being 1
. Its factorization is
In hexadecimal, as well as all higher bases, fifteen is represented as F. Fifteen is the magic result of a 3 by 3 magic square:
Fifteen is also:
- The atomic number of phosphorous.
- The number of guns in a gun salute to Army, Air Force and Marine Corps Lieutenant Generals, and Navy and Coast Guard Vice Admirals.
- The designation of Interstate 15, a freeway that runs from California to Montana.
- The age of a quinceañera, a Hispanic girl celebrating her fifteenth birthday.
- The age for obtaining a driver's permit in jurisdictions where the age for a driver's license is sixteen.
- The number of players on a rugby union team.
See also: thirteen
, fifteen, sixteen
, list of numbers
This article is about the number. For the year AD 15, see 15. For information on the television program, see Fifteen (TV show)