31312121201213 has 4 divisors (see below), whose sum is σ = 31312520939040. Its totient is φ = 31311721463388.

The previous prime is 31312121201201. The next prime is 31312121201227. The reversal of 31312121201213 is 31210212121313.

It is a happy number.

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 31312121201213 - 2⁸ = 31312121200957 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 (31312121281213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199751393 + ... + 199908086.

It is an arithmetic number, because the mean of its divisors is an integer number (7828130234760).

Almost surely, 2^{31312121201213} is an apocalyptic number.

It is an amenable number.

31312121201213 is a deficient number, since it is larger than the sum of its proper divisors (399737827).

31312121201213 is an equidigital number, since it uses as much as digits as its factorization.

31312121201213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399737826.

The product of its (nonzero) digits is 432, while the sum is 23.

Adding to 31312121201213 its reverse (31210212121313), we get a palindrome (62522333322526).

The spelling of 31312121201213 in words is "thirty-one trillion, three hundred twelve billion, one hundred twenty-one million, two hundred one thousand, two hundred thirteen".