31211201213 has 4 divisors (see below), whose sum is σ = 31514222688. Its totient is φ = 30908179740.

The previous prime is 31211201191. The next prime is 31211201261. The reversal of 31211201213 is 31210211213.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31211201213 - 2²⁰ = 31210152637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31211201191 and 31211201200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31211201113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151510583 + ... + 151510788.

It is an arithmetic number, because the mean of its divisors is an integer number (7878555672).

Almost surely, 2^31211201213 is an apocalyptic number.

It is an amenable number.

31211201213 is a deficient number, since it is larger than the sum of its proper divisors (303021475).

31211201213 is a wasteful number, since it uses less digits than its factorization.

31211201213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303021474.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 31211201213 its reverse (31210211213), we get a palindrome (62421412426).

The spelling of 31211201213 in words is "thirty-one billion, two hundred eleven million, two hundred one thousand, two hundred thirteen".