256442660 has 12 divisors (see below), whose sum is σ = 538529628. Its totient is φ = 102577056.

The previous prime is 256442657. The next prime is 256442687. The reversal of 256442660 is 66244652.

It can be written as a sum of positive squares in 2 ways, for example, as 72352036 + 184090624 = 8506^2 + 13568^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 256442660.

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, 6411047 + ... + 6411086.

It is an arithmetic number, because the mean of its divisors is an integer number (44877469).

Almost surely, 2^256442660 is an apocalyptic number.

256442660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256442660 is an abundant number, since it is smaller than the sum of its proper divisors (282086968).

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

256442660 is a wasteful number, since it uses less digits than its factorization.

256442660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12822142 (or 12822140 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 35.

The square root of 256442660 is about 16013.8271503098. The cubic root of 256442660 is about 635.3261886665.

The spelling of 256442660 in words is "two hundred fifty-six million, four hundred forty-two thousand, six hundred sixty".