816515575680 has 256 divisors, whose sum is σ = 2975213813760. Its totient is φ = 186584186880.

The previous prime is 816515575663. The next prime is 816515575697. The reversal of 816515575680 is 86575515618.

It is an interprime number because it is at equal distance from previous prime (816515575663) and next prime (816515575697).

It is a self number, because there is not a number n which added to its sum of digits gives 816515575680.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 99680385 + ... + 99688575.

It is an arithmetic number, because the mean of its divisors is an integer number (11621928960).

Almost surely, 2^816515575680 is an apocalyptic number.

816515575680 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 816515575680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1487606906880).

816515575680 is an abundant number, since it is smaller than the sum of its proper divisors (2158698238080).

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

816515575680 is a wasteful number, since it uses less digits than its factorization.

816515575680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15637 (or 15625 counting only the distinct ones).

The product of its (nonzero) digits is 10080000, while the sum is 57.

The spelling of 816515575680 in words is "eight hundred sixteen billion, five hundred fifteen million, five hundred seventy-five thousand, six hundred eighty".