31500379872 has 96 divisors (see below), whose sum is σ = 98943536160. Its totient is φ = 9692421120.

The previous prime is 31500379871. The next prime is 31500379873. The reversal of 31500379872 is 27897300513.

It is a happy number.

31500379872 is a `hidden beast` number, since 3 + 1 + 500 + 3 + 79 + 8 + 72 = 666.

It is an interprime number because it is at equal distance from previous prime (31500379871) and next prime (31500379873).

It is a tau number, because it is divible by the number of its divisors (96).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31500379871) 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 15 ways as a sum of consecutive naturals, for example, 1391029 + ... + 1413492.

It is an arithmetic number, because the mean of its divisors is an integer number (1030661835).

Almost surely, 2^31500379872 is an apocalyptic number.

31500379872 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

31500379872 is an abundant number, since it is smaller than the sum of its proper divisors (67443156288).

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

31500379872 is a wasteful number, since it uses less digits than its factorization.

31500379872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2804553 (or 2804539 counting only the distinct ones).

The product of its (nonzero) digits is 317520, while the sum is 45.

The spelling of 31500379872 in words is "thirty-one billion, five hundred million, three hundred seventy-nine thousand, eight hundred seventy-two".