256445530631 has 4 divisors (see below), whose sum is σ = 256622025912. Its totient is φ = 256269035352.

The previous prime is 256445530613. The next prime is 256445530633. The reversal of 256445530631 is 136035544652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 256445530631 - 2¹⁰ = 256445529607 is a prime.

It is a super-2 number, since 2×256445530631² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256445530633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88245461 + ... + 88248366.

It is an arithmetic number, because the mean of its divisors is an integer number (64155506478).

Almost surely, 2^256445530631 is an apocalyptic number.

256445530631 is a deficient number, since it is larger than the sum of its proper divisors (176495281).

256445530631 is a wasteful number, since it uses less digits than its factorization.

256445530631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176495280.

The product of its (nonzero) digits is 1296000, while the sum is 44.

The spelling of 256445530631 in words is "two hundred fifty-six billion, four hundred forty-five million, five hundred thirty thousand, six hundred thirty-one".