255906 has 32 divisors (see below), whose sum is σ = 650880. Its totient is φ = 73008.

The previous prime is 255887. The next prime is 255907. The reversal of 255906 is 609552.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 255906.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 255906.

It is not an unprimeable number, because it can be changed into a prime (255907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40 + ... + 716.

It is an arithmetic number, because the mean of its divisors is an integer number (20340).

2²⁵⁵⁹⁰⁶ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 255906, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (325440).

255906 is an abundant number, since it is smaller than the sum of its proper divisors (394974).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

255906 is a wasteful number, since it uses less digits than its factorization.

255906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 695 (or 689 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 255906 is about 505.8715251919. The cubic root of 255906 is about 63.4882694763.

The spelling of 255906 in words is "two hundred fifty-five thousand, nine hundred six".