31213233 has 12 divisors (see below), whose sum is σ = 45721728. Its totient is φ = 20515320.

The previous prime is 31213213. The next prime is 31213243. The reversal of 31213233 is 33231213.

It is not a de Polignac number, because 31213233 - 2⁵ = 31213201 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31213213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23785 + ... + 25062.

It is an arithmetic number, because the mean of its divisors is an integer number (3810144).

Almost surely, 2^31213233 is an apocalyptic number.

It is an amenable number.

31213233 is a deficient number, since it is larger than the sum of its proper divisors (14508495).

31213233 is a wasteful number, since it uses less digits than its factorization.

31213233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48924 (or 48921 counting only the distinct ones).

The product of its digits is 324, while the sum is 18.

The square root of 31213233 is about 5586.8804354487. The cubic root of 31213233 is about 314.8566846168.

Adding to 31213233 its reverse (33231213), we get a palindrome (64444446).

The spelling of 31213233 in words is "thirty-one million, two hundred thirteen thousand, two hundred thirty-three".