81707517360 has 480 divisors, whose sum is σ = 326019133440. Its totient is φ = 17948915712.

The previous prime is 81707517349. The next prime is 81707517383. The reversal of 81707517360 is 6371570718.

81707517360 is a `hidden beast` number, since 8 + 1 + 70 + 7 + 517 + 3 + 60 = 666.

It is a super-2 number, since 2×81707517360² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 15475201 + ... + 15480479.

It is an arithmetic number, because the mean of its divisors is an integer number (679206528).

Almost surely, 2^81707517360 is an apocalyptic number.

81707517360 is a gapful number since it is divisible by the number (80) 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 81707517360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163009566720).

81707517360 is an abundant number, since it is smaller than the sum of its proper divisors (244311616080).

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

81707517360 is a wasteful number, since it uses less digits than its factorization.

81707517360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5425 (or 5416 counting only the distinct ones).

The product of its (nonzero) digits is 246960, while the sum is 45.

The spelling of 81707517360 in words is "eighty-one billion, seven hundred seven million, five hundred seventeen thousand, three hundred sixty".