138899668 has 12 divisors (see below), whose sum is σ = 253643040. Its totient is φ = 66430232.

The previous prime is 138899653. The next prime is 138899669. The reversal of 138899668 is 866998831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138899669) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 754798 + ... + 754981.

It is an arithmetic number, because the mean of its divisors is an integer number (21136920).

Almost surely, 2^138899668 is an apocalyptic number.

It is an amenable number.

138899668 is a deficient number, since it is larger than the sum of its proper divisors (114743372).

138899668 is a wasteful number, since it uses less digits than its factorization.

138899668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1509806 (or 1509804 counting only the distinct ones).

The product of its digits is 4478976, while the sum is 58.

The square root of 138899668 is about 11785.5703298568. The cubic root of 138899668 is about 517.8854812608.

The spelling of 138899668 in words is "one hundred thirty-eight million, eight hundred ninety-nine thousand, six hundred sixty-eight".