256161537 has 6 divisors (see below), whose sum is σ = 370011122. Its totient is φ = 170774352.

The previous prime is 256161533. The next prime is 256161541. The reversal of 256161537 is 735161652.

256161537 is a `hidden beast` number, since 2 + 5 + 6 + 1 + 615 + 37 = 666.

It is an interprime number because it is at equal distance from previous prime (256161533) and next prime (256161541).

It can be written as a sum of positive squares in only one way, i.e., 242611776 + 13549761 = 15576^2 + 3681^2 .

It is not a de Polignac number, because 256161537 - 2² = 256161533 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256161533) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 14231188 + ... + 14231205.

Almost surely, 2^256161537 is an apocalyptic number.

It is an amenable number.

256161537 is a deficient number, since it is larger than the sum of its proper divisors (113849585).

256161537 is a wasteful number, since it uses less digits than its factorization.

256161537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28462399 (or 28462396 counting only the distinct ones).

The product of its digits is 37800, while the sum is 36.

The square root of 256161537 is about 16005.0472351693. The cubic root of 256161537 is about 635.0939468747.

It can be divided in two parts, 2561615 and 37, that added together give a palindrome (2561652).

The spelling of 256161537 in words is "two hundred fifty-six million, one hundred sixty-one thousand, five hundred thirty-seven".