81517363200 has 1440 divisors, whose sum is σ = 373155838720. Its totient is φ = 17199267840.

The previous prime is 81517363183. The next prime is 81517363303. The reversal of 81517363200 is 236371518.

81517363200 is a `hidden beast` number, since 8 + 1 + 5 + 17 + 3 + 632 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 6270566394 + ... + 6270566406.

Almost surely, 2^81517363200 is an apocalyptic number.

81517363200 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 81517363200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (186577919360).

81517363200 is an abundant number, since it is smaller than the sum of its proper divisors (291638475520).

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

81517363200 is an frugal number, since it uses more digits than its factorization.

81517363200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The spelling of 81517363200 in words is "eighty-one billion, five hundred seventeen million, three hundred sixty-three thousand, two hundred".