256260591 has 40 divisors (see below), whose sum is σ = 396152064. Its totient is φ = 164987280.

The previous prime is 256260569. The next prime is 256260629. The reversal of 256260591 is 195062652.

256260591 is a `hidden beast` number, since 2 + 5 + 6 + 2 + 60 + 591 = 666.

It is not a de Polignac number, because 256260591 - 2⁷ = 256260463 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256260551) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 315576 + ... + 316386.

Almost surely, 2^256260591 is an apocalyptic number.

256260591 is a deficient number, since it is larger than the sum of its proper divisors (139891473).

256260591 is an equidigital number, since it uses as much as digits as its factorization.

256260591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 953 (or 944 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 256260591 is about 16008.1413974265. The cubic root of 256260591 is about 635.1757969053.

The spelling of 256260591 in words is "two hundred fifty-six million, two hundred sixty thousand, five hundred ninety-one".