639556012 has 6 divisors (see below), whose sum is σ = 1119223028. Its totient is φ = 319778004.

The previous prime is 639555977. The next prime is 639556019. The reversal of 639556012 is 210655936.

It is not an unprimeable number, because it can be changed into a prime (639556019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79944498 + ... + 79944505.

Almost surely, 2^639556012 is an apocalyptic number.

It is an amenable number.

639556012 is a deficient number, since it is larger than the sum of its proper divisors (479667016).

639556012 is a wasteful number, since it uses less digits than its factorization.

639556012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159889007 (or 159889005 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 37.

The square root of 639556012 is about 25289.4446755954. Note that the first 3 decimals coincide. The cubic root of 639556012 is about 861.5745500900.

The spelling of 639556012 in words is "six hundred thirty-nine million, five hundred fifty-six thousand, twelve".