256660856 has 16 divisors (see below), whose sum is σ = 489396600. Its totient is φ = 126155104.

The previous prime is 256660837. The next prime is 256660867. The reversal of 256660856 is 658066652.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 271415 + ... + 272358.

Almost surely, 2^256660856 is an apocalyptic number.

It is an amenable number.

256660856 is a deficient number, since it is larger than the sum of its proper divisors (232735744).

256660856 is a wasteful number, since it uses less digits than its factorization.

256660856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 543838 (or 543834 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 44.

The square root of 256660856 is about 16020.6384392133. The cubic root of 256660856 is about 635.5063281367.

The spelling of 256660856 in words is "two hundred fifty-six million, six hundred sixty thousand, eight hundred fifty-six".