256868 has 6 divisors (see below), whose sum is σ = 449526. Its totient is φ = 128432.

The previous prime is 256831. The next prime is 256873. The reversal of 256868 is 868652.

It can be written as a sum of positive squares in only one way, i.e., 195364 + 61504 = 442^2 + 248^2 .

It is a nialpdrome in base 8.

It is an unprimeable number.

256868 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 as a sum of consecutive naturals, namely, 32105 + ... + 32112.

It is an arithmetic number, because the mean of its divisors is an integer number (74921).

2²⁵⁶⁸⁶⁸ is an apocalyptic number.

It is an amenable number.

256868 is a deficient number, since it is larger than the sum of its proper divisors (192658).

256868 is a wasteful number, since it uses less digits than its factorization.

256868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64221 (or 64219 counting only the distinct ones).

The product of its digits is 23040, while the sum is 35.

The square root of 256868 is about 506.8214675801. The cubic root of 256868 is about 63.5677248791.

The spelling of 256868 in words is "two hundred fifty-six thousand, eight hundred sixty-eight".