31820517872 has 240 divisors, whose sum is σ = 75654220320. Its totient is φ = 12843417600.

The previous prime is 31820517853. The next prime is 31820517887. The reversal of 31820517872 is 27871502813.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 118291754 + ... + 118292022.

It is an arithmetic number, because the mean of its divisors is an integer number (315225918).

Almost surely, 2^31820517872 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31820517872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37827110160).

31820517872 is an abundant number, since it is smaller than the sum of its proper divisors (43833702448).

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

31820517872 is a wasteful number, since it uses less digits than its factorization.

31820517872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452 (or 433 counting only the distinct ones).

The product of its (nonzero) digits is 188160, while the sum is 44.

The spelling of 31820517872 in words is "thirty-one billion, eight hundred twenty million, five hundred seventeen thousand, eight hundred seventy-two".