31871368920 has 128 divisors (see below), whose sum is σ = 97853184000. Its totient is φ = 8302210560.

The previous prime is 31871368897. The next prime is 31871368933. The reversal of 31871368920 is 2986317813.

It is a hoax number, since the sum of its digits (48) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 31871368920.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 911521 + ... + 945839.

It is an arithmetic number, because the mean of its divisors is an integer number (764478000).

Almost surely, 2^31871368920 is an apocalyptic number.

31871368920 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 31871368920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48926592000).

31871368920 is an abundant number, since it is smaller than the sum of its proper divisors (65981815080).

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

31871368920 is a wasteful number, since it uses less digits than its factorization.

31871368920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34513 (or 34509 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 48.

The spelling of 31871368920 in words is "thirty-one billion, eight hundred seventy-one million, three hundred sixty-eight thousand, nine hundred twenty".