639416980 has 24 divisors (see below), whose sum is σ = 1379068488. Its totient is φ = 248853888.

The previous prime is 639416959. The next prime is 639416989. The reversal of 639416980 is 89614936.

It can be written as a sum of positive squares in 4 ways, for example, as 162256644 + 477160336 = 12738^2 + 21844^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 639416980.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639416989) 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, 431299 + ... + 432778.

It is an arithmetic number, because the mean of its divisors is an integer number (57461187).

Almost surely, 2^639416980 is an apocalyptic number.

It is an amenable number.

639416980 is an abundant number, since it is smaller than the sum of its proper divisors (739651508).

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

639416980 is a wasteful number, since it uses less digits than its factorization.

639416980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 864123 (or 864121 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 46.

The square root of 639416980 is about 25286.6957113815. The cubic root of 639416980 is about 861.5121134873.

The spelling of 639416980 in words is "six hundred thirty-nine million, four hundred sixteen thousand, nine hundred eighty".