256918646 has 24 divisors (see below), whose sum is σ = 408105864. Its totient is φ = 121286880.

The previous prime is 256918631. The next prime is 256918657. The reversal of 256918646 is 646819652.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 256918646.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 375821 + ... + 376503.

It is an arithmetic number, because the mean of its divisors is an integer number (17004411).

Almost surely, 2^256918646 is an apocalyptic number.

256918646 is a deficient number, since it is larger than the sum of its proper divisors (151187218).

256918646 is a wasteful number, since it uses less digits than its factorization.

256918646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1244 (or 1225 counting only the distinct ones).

The product of its digits is 622080, while the sum is 47.

The square root of 256918646 is about 16028.6819795016. The cubic root of 256918646 is about 635.7190243255.

The spelling of 256918646 in words is "two hundred fifty-six million, nine hundred eighteen thousand, six hundred forty-six".