31131212311020 has 48 divisors (see below), whose sum is σ = 87223307109120. Its totient is φ = 8296331603136.

The previous prime is 31131212311009. The next prime is 31131212311033. The reversal of 31131212311020 is 2011321213113.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 166312342 + ... + 166499421.

It is an arithmetic number, because the mean of its divisors is an integer number (1817152231440).

Almost surely, 2^{31131212311020} is an apocalyptic number.

31131212311020 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31131212311020 is an abundant number, since it is smaller than the sum of its proper divisors (56092094798100).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31131212311020 is a wasteful number, since it uses less digits than its factorization.

31131212311020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332813334 (or 332813332 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 21.

Adding to 31131212311020 its reverse (2011321213113), we get a palindrome (33142533524133).

The spelling of 31131212311020 in words is "thirty-one trillion, one hundred thirty-one billion, two hundred twelve million, three hundred eleven thousand, twenty".