639646948 has 12 divisors (see below), whose sum is σ = 1120008960. Its totient is φ = 319644392.

The previous prime is 639646937. The next prime is 639646957. The reversal of 639646948 is 849646936.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36568 + ... + 51151.

It is an arithmetic number, because the mean of its divisors is an integer number (93334080).

Almost surely, 2^639646948 is an apocalyptic number.

It is an amenable number.

639646948 is a deficient number, since it is larger than the sum of its proper divisors (480362012).

639646948 is a wasteful number, since it uses less digits than its factorization.

639646948 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89546 (or 89544 counting only the distinct ones).

The product of its digits is 6718464, while the sum is 55.

The square root of 639646948 is about 25291.2425159382. The cubic root of 639646948 is about 861.6153828077.

The spelling of 639646948 in words is "six hundred thirty-nine million, six hundred forty-six thousand, nine hundred forty-eight".