138508645 has 32 divisors (see below), whose sum is σ = 190439424. Its totient is φ = 95726400.

The previous prime is 138508637. The next prime is 138508661. The reversal of 138508645 is 546805831.

It is not a de Polignac number, because 138508645 - 2³ = 138508637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138508598 and 138508607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 281850 + ... + 282340.

It is an arithmetic number, because the mean of its divisors is an integer number (5951232).

Almost surely, 2^138508645 is an apocalyptic number.

It is an amenable number.

138508645 is a deficient number, since it is larger than the sum of its proper divisors (51930779).

138508645 is a wasteful number, since it uses less digits than its factorization.

138508645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 753.

The product of its (nonzero) digits is 115200, while the sum is 40.

The square root of 138508645 is about 11768.9695810636. The cubic root of 138508645 is about 517.3990499097.

The spelling of 138508645 in words is "one hundred thirty-eight million, five hundred eight thousand, six hundred forty-five".