31161717688320 has 384 divisors, whose sum is σ = 117286078291200. Its totient is φ = 7820978946048.

The previous prime is 31161717688319. The next prime is 31161717688349. The reversal of 31161717688320 is 2388671716113.

31161717688320 is a `hidden beast` number, since 3 + 1 + 1 + 6 + 171 + 76 + 88 + 320 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1385197 + ... + 8015123.

It is an arithmetic number, because the mean of its divisors is an integer number (305432495550).

Almost surely, 2^{31161717688320} is an apocalyptic number.

31161717688320 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 31161717688320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58643039145600).

31161717688320 is an abundant number, since it is smaller than the sum of its proper divisors (86124360602880).

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

31161717688320 is a wasteful number, since it uses less digits than its factorization.

31161717688320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6629980 (or 6629954 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The spelling of 31161717688320 in words is "thirty-one trillion, one hundred sixty-one billion, seven hundred seventeen million, six hundred eighty-eight thousand, three hundred twenty".