256624638 has 32 divisors (see below), whose sum is σ = 525521952. Its totient is φ = 83520000.

The previous prime is 256624607. The next prime is 256624649. The reversal of 256624638 is 836426652.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 256624638.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41338 + ... + 47138.

It is an arithmetic number, because the mean of its divisors is an integer number (16422561).

Almost surely, 2^256624638 is an apocalyptic number.

256624638 is an abundant number, since it is smaller than the sum of its proper divisors (268897314).

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

256624638 is a wasteful number, since it uses less digits than its factorization.

256624638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5980.

The product of its digits is 414720, while the sum is 42.

The square root of 256624638 is about 16019.5080448808. The cubic root of 256624638 is about 635.4764341471.

The spelling of 256624638 in words is "two hundred fifty-six million, six hundred twenty-four thousand, six hundred thirty-eight".