639139196 has 6 divisors (see below), whose sum is σ = 1118493600. Its totient is φ = 319569596.

The previous prime is 639139169. The next prime is 639139199. The reversal of 639139196 is 691931936.

It is a self number, because there is not a number n which added to its sum of digits gives 639139196.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639139199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79892396 + ... + 79892403.

It is an arithmetic number, because the mean of its divisors is an integer number (186415600).

Almost surely, 2^639139196 is an apocalyptic number.

It is an amenable number.

639139196 is a deficient number, since it is larger than the sum of its proper divisors (479354404).

639139196 is a wasteful number, since it uses less digits than its factorization.

639139196 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159784803 (or 159784801 counting only the distinct ones).

The product of its digits is 236196, while the sum is 47.

The square root of 639139196 is about 25281.2024239355. The cubic root of 639139196 is about 861.3873389129.

The spelling of 639139196 in words is "six hundred thirty-nine million, one hundred thirty-nine thousand, one hundred ninety-six".