138615123 has 4 divisors (see below), whose sum is σ = 184820168. Its totient is φ = 92410080.

The previous prime is 138615121. The next prime is 138615149. The reversal of 138615123 is 321516831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 321516831 = 3 ⋅107172277.

It is not a de Polignac number, because 138615123 - 2¹ = 138615121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138615121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23102518 + ... + 23102523.

It is an arithmetic number, because the mean of its divisors is an integer number (46205042).

Almost surely, 2^138615123 is an apocalyptic number.

138615123 is a deficient number, since it is larger than the sum of its proper divisors (46205045).

138615123 is an equidigital number, since it uses as much as digits as its factorization.

138615123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46205044.

The product of its digits is 4320, while the sum is 30.

The square root of 138615123 is about 11773.4923875628. The cubic root of 138615123 is about 517.5315988080.

The spelling of 138615123 in words is "one hundred thirty-eight million, six hundred fifteen thousand, one hundred twenty-three".