256516631 has 8 divisors (see below), whose sum is σ = 305908224. Its totient is φ = 210311640.

The previous prime is 256516609. The next prime is 256516633. The reversal of 256516631 is 136615652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 256516631 - 2²² = 252322327 is a prime.

It is a super-2 number, since 2×256516631² = 131601563959180322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 256516591 and 256516600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256516633) 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 7 ways as a sum of consecutive naturals, for example, 796475 + ... + 796796.

It is an arithmetic number, because the mean of its divisors is an integer number (38238528).

Almost surely, 2^256516631 is an apocalyptic number.

256516631 is a deficient number, since it is larger than the sum of its proper divisors (49391593).

256516631 is a wasteful number, since it uses less digits than its factorization.

256516631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1593301.

The product of its digits is 32400, while the sum is 35.

The square root of 256516631 is about 16016.1365815855. The cubic root of 256516631 is about 635.3872695017.

The spelling of 256516631 in words is "two hundred fifty-six million, five hundred sixteen thousand, six hundred thirty-one".