816975720000 has 1260 divisors, whose sum is σ = 3326546301936. Its totient is φ = 197354880000.

The previous prime is 816975719939. The next prime is 816975720047. The reversal of 816975720000 is 27579618.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 179 ways as a sum of consecutive naturals, for example, 2886839859 + ... + 2886840141.

Almost surely, 2^816975720000 is an apocalyptic number.

816975720000 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 816975720000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1663273150968).

816975720000 is an abundant number, since it is smaller than the sum of its proper divisors (2509570581936).

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

816975720000 is an frugal number, since it uses more digits than its factorization.

816975720000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350 (or 304 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 45.

The spelling of 816975720000 in words is "eight hundred sixteen billion, nine hundred seventy-five million, seven hundred twenty thousand".