31811899398912 has 360 divisors, whose sum is σ = 100462712011200. Its totient is φ = 9977665978368.

The previous prime is 31811899398911. The next prime is 31811899399009. The reversal of 31811899398912 is 21989399811813.

31811899398912 is a `hidden beast` number, since 31 + 8 + 118 + 9 + 9 + 398 + 91 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (31811899398911) by changing a digit.

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 39 ways as a sum of consecutive naturals, for example, 1776299014 + ... + 1776316922.

It is an arithmetic number, because the mean of its divisors is an integer number (279063088920).

Almost surely, 2^{31811899398912} is an apocalyptic number.

31811899398912 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31811899398912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50231356005600).

31811899398912 is an abundant number, since it is smaller than the sum of its proper divisors (68650812612288).

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

31811899398912 is a wasteful number, since it uses less digits than its factorization.

31811899398912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22993 (or 22970 counting only the distinct ones).

The product of its digits is 60466176, while the sum is 72.

The spelling of 31811899398912 in words is "thirty-one trillion, eight hundred eleven billion, eight hundred ninety-nine million, three hundred ninety-eight thousand, nine hundred twelve".