31311312212231 has 16 divisors (see below), whose sum is σ = 31922149238880. Its totient is φ = 30704896886400.

The previous prime is 31311312212177. The next prime is 31311312212251. The reversal of 31311312212231 is 13221221311313.

It is a de Polignac number, because none of the positive numbers 2^k-31311312212231 is a prime.

It is a super-2 number, since 2×31311312212231² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31311312212231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31311312212251) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19821281 + ... + 21342581.

It is an arithmetic number, because the mean of its divisors is an integer number (1995134327430).

Almost surely, 2^{31311312212231} is an apocalyptic number.

31311312212231 is a deficient number, since it is larger than the sum of its proper divisors (610837026649).

31311312212231 is a wasteful number, since it uses less digits than its factorization.

31311312212231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1522754.

The product of its digits is 1296, while the sum is 26.

Adding to 31311312212231 its reverse (13221221311313), we get a palindrome (44532533523544).

The spelling of 31311312212231 in words is "thirty-one trillion, three hundred eleven billion, three hundred twelve million, two hundred twelve thousand, two hundred thirty-one".