256561337400 has 96 divisors (see below), whose sum is σ = 816835896240. Its totient is φ = 66567260160.

The previous prime is 256561337327. The next prime is 256561337423. The reversal of 256561337400 is 4733165652.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5756209 + ... + 5800608.

Almost surely, 2^256561337400 is an apocalyptic number.

256561337400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256561337400 is an abundant number, since it is smaller than the sum of its proper divisors (560274558840).

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

256561337400 is a wasteful number, since it uses less digits than its factorization.

256561337400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11556873 (or 11556864 counting only the distinct ones).

The product of its (nonzero) digits is 453600, while the sum is 42.

The spelling of 256561337400 in words is "two hundred fifty-six billion, five hundred sixty-one million, three hundred thirty-seven thousand, four hundred".