138705707 has 4 divisors (see below), whose sum is σ = 158520816. Its totient is φ = 118890600.

The previous prime is 138705701. The next prime is 138705733. The reversal of 138705707 is 707507831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 707507831 = 2099 ⋅337069.

It is a cyclic number.

It is not a de Polignac number, because 138705707 - 2⁸ = 138705451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138705701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9907544 + ... + 9907557.

It is an arithmetic number, because the mean of its divisors is an integer number (39630204).

Almost surely, 2^138705707 is an apocalyptic number.

138705707 is a deficient number, since it is larger than the sum of its proper divisors (19815109).

138705707 is an equidigital number, since it uses as much as digits as its factorization.

138705707 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19815108.

The product of its (nonzero) digits is 41160, while the sum is 38.

The square root of 138705707 is about 11777.3387061764. The cubic root of 138705707 is about 517.6443086699.

The spelling of 138705707 in words is "one hundred thirty-eight million, seven hundred five thousand, seven hundred seven".