636634664 has 16 divisors (see below), whose sum is σ = 1245589920. Its totient is φ = 304477360.

The previous prime is 636634633. The next prime is 636634697. The reversal of 636634664 is 466436636.

It is a happy number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1729802 + ... + 1730169.

It is an arithmetic number, because the mean of its divisors is an integer number (77849370).

Almost surely, 2^636634664 is an apocalyptic number.

It is an amenable number.

636634664 is a deficient number, since it is larger than the sum of its proper divisors (608955256).

636634664 is a wasteful number, since it uses less digits than its factorization.

636634664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3460000 (or 3459996 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 44.

The square root of 636634664 is about 25231.6203205422. The cubic root of 636634664 is about 860.2607213832.

It can be divided in two parts, 636 and 634664, that multiplied together give a palindrome (403646304).

The spelling of 636634664 in words is "six hundred thirty-six million, six hundred thirty-four thousand, six hundred sixty-four".