138979868 has 12 divisors (see below), whose sum is σ = 243759600. Its totient is φ = 69334272.

The previous prime is 138979859. The next prime is 138979891. The reversal of 138979868 is 868979831.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36896 + ... + 40487.

It is an arithmetic number, because the mean of its divisors is an integer number (20313300).

Almost surely, 2^138979868 is an apocalyptic number.

It is an amenable number.

138979868 is a deficient number, since it is larger than the sum of its proper divisors (104779732).

138979868 is a wasteful number, since it uses less digits than its factorization.

138979868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77836 (or 77834 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 59.

The square root of 138979868 is about 11788.9723046583. The cubic root of 138979868 is about 517.9851369448.

The spelling of 138979868 in words is "one hundred thirty-eight million, nine hundred seventy-nine thousand, eight hundred sixty-eight".