816517680880 has 160 divisors (see below), whose sum is σ = 2096865792000. Its totient is φ = 293227699200.

The previous prime is 816517680833. The next prime is 816517680883. The reversal of 816517680880 is 88086715618.

It is a happy number.

It is a super-2 number, since 2×816517680880² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816517680883) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23345646 + ... + 23380594.

It is an arithmetic number, because the mean of its divisors is an integer number (13105411200).

Almost surely, 2^816517680880 is an apocalyptic number.

816517680880 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 816517680880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1048432896000).

816517680880 is an abundant number, since it is smaller than the sum of its proper divisors (1280348111120).

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

816517680880 is a wasteful number, since it uses less digits than its factorization.

816517680880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35303 (or 35297 counting only the distinct ones).

The product of its (nonzero) digits is 5160960, while the sum is 58.

The spelling of 816517680880 in words is "eight hundred sixteen billion, five hundred seventeen million, six hundred eighty thousand, eight hundred eighty".