63991667631 has 64 divisors (see below), whose sum is σ = 93397708800. Its totient is φ = 38815096320.

The previous prime is 63991667627. The next prime is 63991667653. The reversal of 63991667631 is 13676619936.

It is not a de Polignac number, because 63991667631 - 2² = 63991667627 is a prime.

It is a super-2 number, since 2×63991667631² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63991669631) 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 63 ways as a sum of consecutive naturals, for example, 144450496 + ... + 144450938.

It is an arithmetic number, because the mean of its divisors is an integer number (1459339200).

Almost surely, 2^63991667631 is an apocalyptic number.

63991667631 is a deficient number, since it is larger than the sum of its proper divisors (29406041169).

63991667631 is a wasteful number, since it uses less digits than its factorization.

63991667631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1036.

The product of its digits is 6613488, while the sum is 57.

The spelling of 63991667631 in words is "sixty-three billion, nine hundred ninety-one million, six hundred sixty-seven thousand, six hundred thirty-one".