811993368800 has 144 divisors (see below), whose sum is σ = 2021744506320. Its totient is φ = 318343434240.

The previous prime is 811993368779. The next prime is 811993368803. The reversal of 811993368800 is 8863399118.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (811993368803) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43789931 + ... + 43808469.

It is an arithmetic number, because the mean of its divisors is an integer number (14039892405).

Almost surely, 2^811993368800 is an apocalyptic number.

811993368800 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 811993368800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1010872253160).

811993368800 is an abundant number, since it is smaller than the sum of its proper divisors (1209751137520).

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

811993368800 is a wasteful number, since it uses less digits than its factorization.

811993368800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19645 (or 19632 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 56.

The spelling of 811993368800 in words is "eight hundred eleven billion, nine hundred ninety-three million, three hundred sixty-eight thousand, eight hundred".