131231020123 has 4 divisors (see below), whose sum is σ = 149978308720. Its totient is φ = 112483731528.

The previous prime is 131231020069. The next prime is 131231020157. The reversal of 131231020123 is 321020132131.

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

It is not a de Polignac number, because 131231020123 - 2²⁵ = 131197465691 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 131231020123.

It is not an unprimeable number, because it can be changed into a prime (131231020183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9373644288 + ... + 9373644301.

It is an arithmetic number, because the mean of its divisors is an integer number (37494577180).

Almost surely, 2^131231020123 is an apocalyptic number.

131231020123 is a deficient number, since it is larger than the sum of its proper divisors (18747288597).

131231020123 is an equidigital number, since it uses as much as digits as its factorization.

131231020123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18747288596.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 131231020123 its reverse (321020132131), we get a palindrome (452251152254).

The spelling of 131231020123 in words is "one hundred thirty-one billion, two hundred thirty-one million, twenty thousand, one hundred twenty-three".