31512100000000 has 324 divisors, whose sum is σ = 79106152857004. Its totient is φ = 12528000000000.

The previous prime is 31512099999997. The next prime is 31512100000061. The reversal of 31512100000000 is 121513.

It can be written as a sum of positive squares in 18 ways, for example, as 7191579250944 + 24320520749056 = 2681712^2 + 4931584^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 18099999130 + ... + 18100000870.

Almost surely, 2^{31512100000000} 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 31512100000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39553076428502).

31512100000000 is an abundant number, since it is smaller than the sum of its proper divisors (47594052857004).

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

31512100000000 is an frugal number, since it uses more digits than its factorization.

31512100000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1978 (or 1929 counting only the distinct ones).

The product of its (nonzero) digits is 30, while the sum is 13.

Adding to 31512100000000 its reverse (121513), we get a palindrome (31512100121513).

The spelling of 31512100000000 in words is "thirty-one trillion, five hundred twelve billion, one hundred million", and thus it is an aban number.