81716593956 has 24 divisors (see below), whose sum is σ = 201888056160. Its totient is φ = 25636578432.

The previous prime is 81716593943. The next prime is 81716593957. The reversal of 81716593956 is 65939561718.

It is a self number, because there is not a number n which added to its sum of digits gives 81716593956.

It is not an unprimeable number, because it can be changed into a prime (81716593957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 200285566 + ... + 200285973.

It is an arithmetic number, because the mean of its divisors is an integer number (8412002340).

Almost surely, 2^81716593956 is an apocalyptic number.

It is an amenable number.

81716593956 is an abundant number, since it is smaller than the sum of its proper divisors (120171462204).

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

81716593956 is a wasteful number, since it uses less digits than its factorization.

81716593956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400571563 (or 400571561 counting only the distinct ones).

The product of its digits is 12247200, while the sum is 60.

The spelling of 81716593956 in words is "eighty-one billion, seven hundred sixteen million, five hundred ninety-three thousand, nine hundred fifty-six".