800 (number)

800 (eight hundred) is the Natural number following 799 and preceding 801.

Cardinal number 800 eight hundred
Ordinal number 800th eight hundredth
Roman numeral DCCC
Roman numeral (Unicode) DCCC, dccc
Binary numeral system 1100100000
Octal 1440
Duodecimal 568
Hexadecimal 320
It is the sum of four consecutive primes (193 + 197 + 199 + 211). It is a Harshad number.

Eight hundred is also:
The original Toll-free Area code for telephone calls in the North American Numbering Plan and some other countries.
The International direct dial code for toll-free international phone calls.
In the ISO rating standard (aka ISO 5800), a common Film speed for Photographic film.
The flight number of TWA Flight 800
The Atari 8-bit family home computer.
A perfect score on an individual section of the SAT test or on one of the SAT Subject Tests.
The distance in meters of an athletic event (the 800m).

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