138688707 has 4 divisors (see below), whose sum is σ = 184918280. Its totient is φ = 92459136.

The previous prime is 138688673. The next prime is 138688721. The reversal of 138688707 is 707886831.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 138688707 - 2²⁰ = 137640131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138688777) 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, 23114782 + ... + 23114787.

It is an arithmetic number, because the mean of its divisors is an integer number (46229570).

Almost surely, 2^138688707 is an apocalyptic number.

138688707 is a deficient number, since it is larger than the sum of its proper divisors (46229573).

138688707 is an equidigital number, since it uses as much as digits as its factorization.

138688707 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46229572.

The product of its (nonzero) digits is 451584, while the sum is 48.

The square root of 138688707 is about 11776.6169590422. The cubic root of 138688707 is about 517.6231600261.

The spelling of 138688707 in words is "one hundred thirty-eight million, six hundred eighty-eight thousand, seven hundred seven".