639369685574 has 4 divisors (see below), whose sum is σ = 959054528364. Its totient is φ = 319684842786.

The previous prime is 639369685567. The next prime is 639369685583. The reversal of 639369685574 is 475586963936.

639369685574 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 639369685498 and 639369685507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159842421392 + ... + 159842421395.

It is an arithmetic number, because the mean of its divisors is an integer number (239763632091).

Almost surely, 2^639369685574 is an apocalyptic number.

639369685574 is a deficient number, since it is larger than the sum of its proper divisors (319684842790).

639369685574 is a wasteful number, since it uses less digits than its factorization.

639369685574 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319684842789.

The product of its digits is 881798400, while the sum is 71.

The spelling of 639369685574 in words is "six hundred thirty-nine billion, three hundred sixty-nine million, six hundred eighty-five thousand, five hundred seventy-four".