138865864 has 32 divisors (see below), whose sum is σ = 270950400. Its totient is φ = 66648960.

The previous prime is 138865849. The next prime is 138865897. The reversal of 138865864 is 468568831.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29292 + ... + 33700.

It is an arithmetic number, because the mean of its divisors is an integer number (8467200).

Almost surely, 2^138865864 is an apocalyptic number.

It is an amenable number.

138865864 is a deficient number, since it is larger than the sum of its proper divisors (132084536).

138865864 is a wasteful number, since it uses less digits than its factorization.

138865864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4573 (or 4569 counting only the distinct ones).

The product of its digits is 1105920, while the sum is 49.

The square root of 138865864 is about 11784.1361159824. The cubic root of 138865864 is about 517.8434652708.

The spelling of 138865864 in words is "one hundred thirty-eight million, eight hundred sixty-five thousand, eight hundred sixty-four".