81518602560 has 56 divisors (see below), whose sum is σ = 258821566176. Its totient is φ = 21738293760.

The previous prime is 81518602537. The next prime is 81518602601. The reversal of 81518602560 is 6520681518.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42456646 + ... + 42458565.

Almost surely, 2^81518602560 is an apocalyptic number.

81518602560 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81518602560 is an abundant number, since it is smaller than the sum of its proper divisors (177302963616).

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

81518602560 is a wasteful number, since it uses less digits than its factorization.

81518602560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84915231 (or 84915221 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 42.

The spelling of 81518602560 in words is "eighty-one billion, five hundred eighteen million, six hundred two thousand, five hundred sixty".