23131321221 has 16 divisors (see below), whose sum is σ = 32471436800. Its totient is φ = 14606364528.

The previous prime is 23131321217. The next prime is 23131321253. The reversal of 23131321221 is 12212313132.

It is not a de Polignac number, because 23131321221 - 2² = 23131321217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23131321021) 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, 271440 + ... + 346326.

It is an arithmetic number, because the mean of its divisors is an integer number (2029464800).

Almost surely, 2^23131321221 is an apocalyptic number.

It is an amenable number.

23131321221 is a deficient number, since it is larger than the sum of its proper divisors (9340115579).

23131321221 is a wasteful number, since it uses less digits than its factorization.

23131321221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80328.

The product of its digits is 432, while the sum is 21.

Adding to 23131321221 its reverse (12212313132), we get a palindrome (35343634353).

The spelling of 23131321221 in words is "twenty-three billion, one hundred thirty-one million, three hundred twenty-one thousand, two hundred twenty-one".