ThirteenThirteen (13) is the natural number following twelve and preceding fourteen.
In base fourteen and higher bases (such as hexadecimal), thirteen is represented as D.
Thirteen is also:
- Regarded as an unlucky number in many cultures. Unreasoned fear of the number 13 is termed triskaidekaphobia. Due to this fear, some tall buildings have resorted to skipping the thirteenth floor or having a 12a-th floor instead. The thirteenth of a month is likewise ominous, at least when it falls on a Friday.
- Regarded as a lucky number in China because it is synonymous with 實生 which means "must be alive". However 13 is regarded as unlucky by those Chinese under the influence of foreign cultures.
There are thirteen loaves in a baker's dozen.
In bingo it is called Unlucky for some.
See also: eleven, twelve, thirteen, fourteen, fifteen integer, list of numbers.
This article is about the number. For the year AD 13, see 13.