81803766326400 has 384 divisors, whose sum is σ = 315135860520000. Its totient is φ = 20666214236160.

The previous prime is 81803766326329. The next prime is 81803766326431. The reversal of 81803766326400 is 462366730818.

81803766326400 is a `hidden beast` number, since 8 + 1 + 8 + 0 + 376 + 6 + 3 + 264 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 23274265 + ... + 26557464.

Almost surely, 2^{81803766326400} is an apocalyptic number.

81803766326400 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81803766326400 is an abundant number, since it is smaller than the sum of its proper divisors (233332094193600).

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

81803766326400 is a wasteful number, since it uses less digits than its factorization.

81803766326400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49831781 (or 49831758 counting only the distinct ones).

The product of its (nonzero) digits is 6967296, while the sum is 54.

The spelling of 81803766326400 in words is "eighty-one trillion, eight hundred three billion, seven hundred sixty-six million, three hundred twenty-six thousand, four hundred".