816771058790400 has 3432 divisors, whose sum is σ = 3627275054538240. Its totient is φ = 178360707317760.

The previous prime is 816771058790399. The next prime is 816771058790419. The reversal of 816771058790400 is 4097850177618.

816771058790400 is a `hidden beast` number, since 8 + 1 + 6 + 7 + 7 + 1 + 0 + 587 + 9 + 0 + 40 + 0 = 666.

It is a super-2 number, since 2×816771058790400² (a number of 31 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 263 ways as a sum of consecutive naturals, for example, 973505433181 + ... + 973505434019.

Almost surely, 2^{816771058790400} is an apocalyptic number.

816771058790400 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 816771058790400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1813637527269120).

816771058790400 is an abundant number, since it is smaller than the sum of its proper divisors (2810503995747840).

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

816771058790400 is an frugal number, since it uses more digits than its factorization.

816771058790400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 933 (or 879 counting only the distinct ones).

The product of its (nonzero) digits is 23708160, while the sum is 63.

The spelling of 816771058790400 in words is "eight hundred sixteen trillion, seven hundred seventy-one billion, fifty-eight million, seven hundred ninety thousand, four hundred".