123531311064138 has 64 divisors (see below), whose sum is σ = 268794240860160. Its totient is φ = 37729191310272.

The previous prime is 123531311064097. The next prime is 123531311064149. The reversal of 123531311064138 is 831460113135321.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 123531311064138.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 121016920 + ... + 122033427.

It is an arithmetic number, because the mean of its divisors is an integer number (4199910013440).

Almost surely, 2^{123531311064138} is an apocalyptic number.

123531311064138 is an abundant number, since it is smaller than the sum of its proper divisors (145262929796022).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

123531311064138 is a wasteful number, since it uses less digits than its factorization.

123531311064138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243050531.

The product of its (nonzero) digits is 155520, while the sum is 42.

Adding to 123531311064138 its reverse (831460113135321), we get a palindrome (954991424199459).

The spelling of 123531311064138 in words is "one hundred twenty-three trillion, five hundred thirty-one billion, three hundred eleven million, sixty-four thousand, one hundred thirty-eight".