639871713 has 24 divisors (see below), whose sum is σ = 1027470080. Its totient is φ = 381062880.

The previous prime is 639871699. The next prime is 639871717. The reversal of 639871713 is 317178936.

639871713 is a `hidden beast` number, since 639 + 8 + 7 + 1 + 7 + 1 + 3 = 666.

It is not a de Polignac number, because 639871713 - 2⁵ = 639871681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (639871717) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 84583 + ... + 91836.

Almost surely, 2^639871713 is an apocalyptic number.

It is an amenable number.

639871713 is a deficient number, since it is larger than the sum of its proper divisors (387598367).

639871713 is a wasteful number, since it uses less digits than its factorization.

639871713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176469 (or 176466 counting only the distinct ones).

The product of its digits is 190512, while the sum is 45.

The square root of 639871713 is about 25295.6856598116. The cubic root of 639871713 is about 861.7162917560.

The spelling of 639871713 in words is "six hundred thirty-nine million, eight hundred seventy-one thousand, seven hundred thirteen".