256664315364631 has 4 divisors (see below), whose sum is σ = 256704946099992. Its totient is φ = 256623684629272.

The previous prime is 256664315364619. The next prime is 256664315364637. The reversal of 256664315364631 is 136463513466652.

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 256664315364631 - 2⁵ = 256664315364599 is a prime.

It is a super-3 number, since 3×256664315364631³ (a number of 44 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256664315364631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256664315364637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20315358205 + ... + 20315370838.

It is an arithmetic number, because the mean of its divisors is an integer number (64176236524998).

Almost surely, 2^{256664315364631} is an apocalyptic number.

256664315364631 is a deficient number, since it is larger than the sum of its proper divisors (40630735361).

256664315364631 is an equidigital number, since it uses as much as digits as its factorization.

256664315364631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40630735360.

The product of its digits is 167961600, while the sum is 61.

The spelling of 256664315364631 in words is "two hundred fifty-six trillion, six hundred sixty-four billion, three hundred fifteen million, three hundred sixty-four thousand, six hundred thirty-one".