31233112221 has 32 divisors (see below), whose sum is σ = 42922012672. Its totient is φ = 20190643200.

The previous prime is 31233112139. The next prime is 31233112237. The reversal of 31233112221 is 12221133213.

It is not a de Polignac number, because 31233112221 - 2¹⁰ = 31233111197 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 (31233112321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16007796 + ... + 16009746.

It is an arithmetic number, because the mean of its divisors is an integer number (1341312896).

Almost surely, 2^31233112221 is an apocalyptic number.

It is an amenable number.

31233112221 is a deficient number, since it is larger than the sum of its proper divisors (11688900451).

31233112221 is a wasteful number, since it uses less digits than its factorization.

31233112221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2833.

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

Adding to 31233112221 its reverse (12221133213), we get a palindrome (43454245434).

The spelling of 31233112221 in words is "thirty-one billion, two hundred thirty-three million, one hundred twelve thousand, two hundred twenty-one".