638788912 has 10 divisors (see below), whose sum is σ = 1237653548. Its totient is φ = 319394448.

The previous prime is 638788907. The next prime is 638788933. The reversal of 638788912 is 219887836.

It is a self number, because there is not a number n which added to its sum of digits gives 638788912.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19962138 + ... + 19962169.

Almost surely, 2^638788912 is an apocalyptic number.

It is an amenable number.

638788912 is a deficient number, since it is larger than the sum of its proper divisors (598864636).

638788912 is a wasteful number, since it uses less digits than its factorization.

638788912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39924315 (or 39924309 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 52.

The square root of 638788912 is about 25274.2737185463. The cubic root of 638788912 is about 861.2299473551.

The spelling of 638788912 in words is "six hundred thirty-eight million, seven hundred eighty-eight thousand, nine hundred twelve".