631688320513 has 4 divisors (see below), whose sum is σ = 631791157248. Its totient is φ = 631585483780.

The previous prime is 631688320493. The next prime is 631688320567. The reversal of 631688320513 is 315023886136.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 631688320513 - 2²⁵ = 631654766081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (631688320573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51409153 + ... + 51421438.

It is an arithmetic number, because the mean of its divisors is an integer number (157947789312).

Almost surely, 2^631688320513 is an apocalyptic number.

It is an amenable number.

631688320513 is a deficient number, since it is larger than the sum of its proper divisors (102836735).

631688320513 is a wasteful number, since it uses less digits than its factorization.

631688320513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102836734.

The product of its (nonzero) digits is 622080, while the sum is 46.

The spelling of 631688320513 in words is "six hundred thirty-one billion, six hundred eighty-eight million, three hundred twenty thousand, five hundred thirteen".