639244384 has 12 divisors (see below), whose sum is σ = 1258512444. Its totient is φ = 319622176.

The previous prime is 639244367. The next prime is 639244399. The reversal of 639244384 is 483442936.

It is a self number, because there is not a number n which added to its sum of digits gives 639244384.

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, 9988162 + ... + 9988225.

It is an arithmetic number, because the mean of its divisors is an integer number (104876037).

Almost surely, 2^639244384 is an apocalyptic number.

It is an amenable number.

639244384 is a deficient number, since it is larger than the sum of its proper divisors (619268060).

639244384 is a wasteful number, since it uses less digits than its factorization.

639244384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19976397 (or 19976389 counting only the distinct ones).

The product of its digits is 497664, while the sum is 43.

The square root of 639244384 is about 25283.2826982574. The cubic root of 639244384 is about 861.4345913433.

The spelling of 639244384 in words is "six hundred thirty-nine million, two hundred forty-four thousand, three hundred eighty-four".