31231122012 has 72 divisors (see below), whose sum is σ = 79297938720. Its totient is φ = 10363991040.

The previous prime is 31231122001. The next prime is 31231122029. The reversal of 31231122012 is 21022113213.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8231988 + ... + 8235780.

It is an arithmetic number, because the mean of its divisors is an integer number (1101360260).

Almost surely, 2^31231122012 is an apocalyptic number.

It is an amenable number.

31231122012 is an abundant number, since it is smaller than the sum of its proper divisors (48066816708).

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

31231122012 is a wasteful number, since it uses less digits than its factorization.

31231122012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4763 (or 4758 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 31231122012 its reverse (21022113213), we get a palindrome (52253235225).

The spelling of 31231122012 in words is "thirty-one billion, two hundred thirty-one million, one hundred twenty-two thousand, twelve".