81318306056400 has 360 divisors, whose sum is σ = 334455837386944. Its totient is φ = 18587041228800.

The previous prime is 81318306056333. The next prime is 81318306056413. The reversal of 81318306056400 is 465060381318.

81318306056400 is a `hidden beast` number, since 8 + 1 + 3 + 1 + 8 + 30 + 605 + 6 + 4 + 0 + 0 = 666.

81318306056400 is digitally balanced in base 3 and base 5, because in such bases it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (360).

It is a super-2 number, since 2×81318306056400² (a number of 29 digits) contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 59077321 + ... + 60438120.

Almost surely, 2^{81318306056400} is an apocalyptic number.

81318306056400 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81318306056400 is an abundant number, since it is smaller than the sum of its proper divisors (253137531330544).

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

81318306056400 is a wasteful number, since it uses less digits than its factorization.

81318306056400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119515481 (or 119515458 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The spelling of 81318306056400 in words is "eighty-one trillion, three hundred eighteen billion, three hundred six million, fifty-six thousand, four hundred".