One thousand (1000) is a natural number.

In scientific notation, it is written as 103. The standard prefix for a thousand is "kilo-".

The Roman numeral for thousand is M (for mille).

See also: millennium

Thousand is also the name of a single released by techno artist Moby, which has the world record for the fastest tempo in beats-per-minute (BPM) of any released single. It clocks in at approximately 1,000 BPM, hence the title of the recording.

Numbers in the Thousands (1000-1999)

;1729 - One thousand seven hundred and twenty nine