31213133213 has 4 divisors (see below), whose sum is σ = 31293373020. Its totient is φ = 31132893408.

The previous prime is 31213133209. The next prime is 31213133221. The reversal of 31213133213 is 31233131213.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5388000409 + 25825132804 = 73403^2 + 160702^2 .

It is a cyclic number.

It is not a de Polignac number, because 31213133213 - 2² = 31213133209 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 (31213133233) 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 3 ways as a sum of consecutive naturals, for example, 40119320 + ... + 40120097.

It is an arithmetic number, because the mean of its divisors is an integer number (7823343255).

Almost surely, 2^31213133213 is an apocalyptic number.

It is an amenable number.

31213133213 is a deficient number, since it is larger than the sum of its proper divisors (80239807).

31213133213 is an equidigital number, since it uses as much as digits as its factorization.

31213133213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80239806.

The product of its digits is 972, while the sum is 23.

Adding to 31213133213 its reverse (31233131213), we get a palindrome (62446264426).

The spelling of 31213133213 in words is "thirty-one billion, two hundred thirteen million, one hundred thirty-three thousand, two hundred thirteen".