31515309016128 has 672 divisors, whose sum is σ = 113502192713728. Its totient is φ = 8478365644800.

The previous prime is 31515309016109. The next prime is 31515309016133. The reversal of 31515309016128 is 82161090351513.

31515309016128 is a `hidden beast` number, since 3 + 1 + 5 + 1 + 530 + 90 + 1 + 6 + 1 + 28 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a super-2 number, since 2×31515309016128² (a number of 28 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 124740813 + ... + 124993203.

Almost surely, 2^{31515309016128} 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 31515309016128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56751096356864).

31515309016128 is an abundant number, since it is smaller than the sum of its proper divisors (81986883697600).

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

31515309016128 is a wasteful number, since it uses less digits than its factorization.

31515309016128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252493 (or 252471 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The spelling of 31515309016128 in words is "thirty-one trillion, five hundred fifteen billion, three hundred nine million, sixteen thousand, one hundred twenty-eight".