639664466936 has 32 divisors (see below), whose sum is σ = 1309539582000. Its totient is φ = 290504355840.

The previous prime is 639664466923. The next prime is 639664466939.

639664466936 is nontrivially palindromic in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639664466939) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3050711 + ... + 3253638.

Almost surely, 2^639664466936 is an apocalyptic number.

It is an amenable number.

639664466936 is an abundant number, since it is smaller than the sum of its proper divisors (669875115064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639664466936 is a wasteful number, since it uses less digits than its factorization.

639664466936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6305519 (or 6305515 counting only the distinct ones).

The product of its digits is 544195584, while the sum is 68.

The spelling of 639664466936 in words is "six hundred thirty-nine billion, six hundred sixty-four million, four hundred sixty-six thousand, nine hundred thirty-six".