138728864 has 24 divisors (see below), whose sum is σ = 274105440. Its totient is φ = 69114816.

The previous prime is 138728797. The next prime is 138728867. The reversal of 138728864 is 468827831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138728867) 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, 1397 + ... + 16715.

It is an arithmetic number, because the mean of its divisors is an integer number (11421060).

Almost surely, 2^138728864 is an apocalyptic number.

It is an amenable number.

138728864 is a deficient number, since it is larger than the sum of its proper divisors (135376576).

138728864 is a wasteful number, since it uses less digits than its factorization.

138728864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15612 (or 15604 counting only the distinct ones).

The product of its digits is 516096, while the sum is 47.

The square root of 138728864 is about 11778.3217819858. The cubic root of 138728864 is about 517.6731140750.

The spelling of 138728864 in words is "one hundred thirty-eight million, seven hundred twenty-eight thousand, eight hundred sixty-four".