31023212120213 has 4 divisors (see below), whose sum is σ = 31096901460588. Its totient is φ = 30949522779840.

The previous prime is 31023212120167. The next prime is 31023212120237. The reversal of 31023212120213 is 31202121232013.

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 6411869715889 + 24611342404324 = 2532167^2 + 4960982^2 .

It is a cyclic number.

It is not a de Polignac number, because 31023212120213 - 2⁴⁰ = 29923700492437 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 (31023212122213) 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, 36844669556 + ... + 36844670397.

It is an arithmetic number, because the mean of its divisors is an integer number (7774225365147).

Almost surely, 2^{31023212120213} is an apocalyptic number.

It is an amenable number.

31023212120213 is a deficient number, since it is larger than the sum of its proper divisors (73689340375).

31023212120213 is an equidigital number, since it uses as much as digits as its factorization.

31023212120213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73689340374.

The product of its (nonzero) digits is 864, while the sum is 23.

Adding to 31023212120213 its reverse (31202121232013), we get a palindrome (62225333352226).

The spelling of 31023212120213 in words is "thirty-one trillion, twenty-three billion, two hundred twelve million, one hundred twenty thousand, two hundred thirteen".