31131100212 has 12 divisors (see below), whose sum is σ = 72639233856. Its totient is φ = 10377033400.

The previous prime is 31131100199. The next prime is 31131100237. The reversal of 31131100212 is 21200113113.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 31131100191 and 31131100200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1297129164 + ... + 1297129187.

It is an arithmetic number, because the mean of its divisors is an integer number (6053269488).

Almost surely, 2^31131100212 is an apocalyptic number.

It is an amenable number.

31131100212 is an abundant number, since it is smaller than the sum of its proper divisors (41508133644).

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

31131100212 is a wasteful number, since it uses less digits than its factorization.

31131100212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2594258358 (or 2594258356 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 31131100212 its reverse (21200113113), we get a palindrome (52331213325).

The spelling of 31131100212 in words is "thirty-one billion, one hundred thirty-one million, one hundred thousand, two hundred twelve".