31317790920 has 256 divisors, whose sum is σ = 104828774400. Its totient is φ = 7432888320.

The previous prime is 31317790913. The next prime is 31317790921. The reversal of 31317790920 is 2909771313.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (31317790921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 15135646 + ... + 15137714.

It is an arithmetic number, because the mean of its divisors is an integer number (409487400).

Almost surely, 2^31317790920 is an apocalyptic number.

31317790920 is a gapful number since it is divisible by the number (30) 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 31317790920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52414387200).

31317790920 is an abundant number, since it is smaller than the sum of its proper divisors (73510983480).

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

31317790920 is a wasteful number, since it uses less digits than its factorization.

31317790920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2440 (or 2436 counting only the distinct ones).

The product of its (nonzero) digits is 71442, while the sum is 42.

The spelling of 31317790920 in words is "thirty-one billion, three hundred seventeen million, seven hundred ninety thousand, nine hundred twenty".