138938785 has 8 divisors (see below), whose sum is σ = 169460136. Its totient is φ = 109328640.

The previous prime is 138938777. The next prime is 138938803. The reversal of 138938785 is 587839831.

It can be written as a sum of positive squares in 4 ways, for example, as 7354944 + 131583841 = 2712^2 + 11471^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 138938785 - 2³ = 138938777 is a prime.

It is a Duffinian number.

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, 227464 + ... + 228073.

It is an arithmetic number, because the mean of its divisors is an integer number (21182517).

Almost surely, 2^138938785 is an apocalyptic number.

It is an amenable number.

138938785 is a deficient number, since it is larger than the sum of its proper divisors (30521351).

138938785 is an equidigital number, since it uses as much as digits as its factorization.

138938785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 455603.

The product of its digits is 1451520, while the sum is 52.

The square root of 138938785 is about 11787.2297423949. The cubic root of 138938785 is about 517.9340924281.

The spelling of 138938785 in words is "one hundred thirty-eight million, nine hundred thirty-eight thousand, seven hundred eighty-five".