256826 has 4 divisors (see below), whose sum is σ = 385242. Its totient is φ = 128412.

The previous prime is 256813. The next prime is 256831. The reversal of 256826 is 628652.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 201601 + 55225 = 449^2 + 235^2 .

It is an unprimeable number.

256826 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64205 + ... + 64208.

2²⁵⁶⁸²⁶ is an apocalyptic number.

256826 is a deficient number, since it is larger than the sum of its proper divisors (128416).

256826 is a wasteful number, since it uses less digits than its factorization.

256826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128415.

The product of its digits is 5760, while the sum is 29.

The square root of 256826 is about 506.7800311772. The cubic root of 256826 is about 63.5642600775.

The spelling of 256826 in words is "two hundred fifty-six thousand, eight hundred twenty-six".