138876638231 has 4 divisors (see below), whose sum is σ = 146185935000. Its totient is φ = 131567341464.

The previous prime is 138876638189. The next prime is 138876638311. The reversal of 138876638231 is 132836678831.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138876638231 is a prime.

It is a super-2 number, since 2×138876638231² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138876638431) 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, 3654648356 + ... + 3654648393.

It is an arithmetic number, because the mean of its divisors is an integer number (36546483750).

Almost surely, 2^138876638231 is an apocalyptic number.

138876638231 is a deficient number, since it is larger than the sum of its proper divisors (7309296769).

138876638231 is an equidigital number, since it uses as much as digits as its factorization.

138876638231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7309296768.

The product of its digits is 6967296, while the sum is 56.

The spelling of 138876638231 in words is "one hundred thirty-eight billion, eight hundred seventy-six million, six hundred thirty-eight thousand, two hundred thirty-one".