256856 has 16 divisors (see below), whose sum is σ = 488040. Its totient is φ = 126720.

The previous prime is 256831. The next prime is 256873. The reversal of 256856 is 658652.

It is a happy number.

It is a nialpdrome in base 8.

It is a congruent number.

It is an unprimeable number.

256856 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 3 ways as a sum of consecutive naturals, for example, 611 + ... + 941.

2²⁵⁶⁸⁵⁶ is an apocalyptic number.

It is an amenable number.

256856 is a deficient number, since it is larger than the sum of its proper divisors (231184).

256856 is a wasteful number, since it uses less digits than its factorization.

256856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434 (or 430 counting only the distinct ones).

The product of its digits is 14400, while the sum is 32.

The square root of 256856 is about 506.8096289535. The cubic root of 256856 is about 63.5667349743.

The spelling of 256856 in words is "two hundred fifty-six thousand, eight hundred fifty-six".