Three hundred ninety nine
399 is an odd number.
399 is a Harshad number, which means it is divisible by the sum of its digits (3 + 9 + 9 = 21, and 399 is divisible by 21).
In binary, 399 is represented as 110001111.
In hex, 399 is represented as 18f.
Prime factorization of 399: 3 * 7 * 19.