81760416560 has 80 divisors (see below), whose sum is σ = 198764064000. Its totient is φ = 31218190080.

The previous prime is 81760416553. The next prime is 81760416671. The reversal of 81760416560 is 6561406718.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 858191 + ... + 948689.

It is an arithmetic number, because the mean of its divisors is an integer number (2484550800).

Almost surely, 2^81760416560 is an apocalyptic number.

81760416560 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 81760416560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99382032000).

81760416560 is an abundant number, since it is smaller than the sum of its proper divisors (117003647440).

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

81760416560 is a wasteful number, since it uses less digits than its factorization.

81760416560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91026 (or 91020 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 44.

The spelling of 81760416560 in words is "eighty-one billion, seven hundred sixty million, four hundred sixteen thousand, five hundred sixty".