138831622781 has 16 divisors (see below), whose sum is σ = 142824584448. Its totient is φ = 134868153600.

The previous prime is 138831622763. The next prime is 138831622801. The reversal of 138831622781 is 187226138831.

It is a cyclic number.

It is not a de Polignac number, because 138831622781 - 2¹⁰ = 138831621757 is a prime.

It is a super-2 number, since 2×138831622781² (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 (138831622751) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32919785 + ... + 32924001.

It is an arithmetic number, because the mean of its divisors is an integer number (8926536528).

Almost surely, 2^138831622781 is an apocalyptic number.

It is an amenable number.

138831622781 is a deficient number, since it is larger than the sum of its proper divisors (3992961667).

138831622781 is a wasteful number, since it uses less digits than its factorization.

138831622781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7492.

The product of its digits is 774144, while the sum is 50.

The spelling of 138831622781 in words is "one hundred thirty-eight billion, eight hundred thirty-one million, six hundred twenty-two thousand, seven hundred eighty-one".