31213312112 has 20 divisors (see below), whose sum is σ = 60509765520. Its totient is φ = 15597888768.

The previous prime is 31213312063. The next prime is 31213312133. The reversal of 31213312112 is 21121331213.

It is a happy number.

It is a super-2 number, since 2×31213312112² (a number of 22 digits) contains 22 as substring.

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, 518537 + ... + 575592.

It is an arithmetic number, because the mean of its divisors is an integer number (3025488276).

Almost surely, 2^31213312112 is an apocalyptic number.

It is an amenable number.

31213312112 is a deficient number, since it is larger than the sum of its proper divisors (29296453408).

31213312112 is a wasteful number, since it uses less digits than its factorization.

31213312112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1095920 (or 1095914 counting only the distinct ones).

The product of its digits is 216, while the sum is 20.

Adding to 31213312112 its reverse (21121331213), we get a palindrome (52334643325).

It can be divided in two parts, 3121331211 and 2, that added together give a palindrome (3121331213).

The spelling of 31213312112 in words is "thirty-one billion, two hundred thirteen million, three hundred twelve thousand, one hundred twelve".