256626 has 24 divisors (see below), whose sum is σ = 568620. Its totient is φ = 83616.

The previous prime is 256609. The next prime is 256639. The reversal of 256626 is 626652.

It can be written as a sum of positive squares in 2 ways, for example, as 251001 + 5625 = 501^2 + 75^2 .

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 256626.

It is an unprimeable number.

256626 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 11 ways as a sum of consecutive naturals, for example, 820 + ... + 1088.

2²⁵⁶⁶²⁶ is an apocalyptic number.

256626 is an abundant number, since it is smaller than the sum of its proper divisors (311994).

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

256626 is a wasteful number, since it uses less digits than its factorization.

256626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330 (or 327 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 256626 is about 506.5826684757. The cubic root of 256626 is about 63.5477558380.

The spelling of 256626 in words is "two hundred fifty-six thousand, six hundred twenty-six".