6 (six) is the natural number following 5 and preceding 7.
The SI prefix for 1000 is exa (E), and for its reciprocal atto (a).
Six is the second smallest composite number, its proper divisors being 1, 2 and 3. Since six equals the sum of these proper divisors, six is the smallest perfect number. As a perfect number, 6 is related to the Mersenne prime 3, since 2(2 - 1) = 6...
Also known as:
- λf.λx. f (f (f (f (f (f x)))))