81313569792000 has 6048 divisors, whose sum is σ = 401411812445280. Its totient is φ = 16253308108800.

The previous prime is 81313569791989. The next prime is 81313569792001. The reversal of 81313569792000 is 29796531318.

81313569792000 is a `hidden beast` number, since 8 + 1 + 3 + 1 + 3 + 569 + 79 + 2 + 0 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (6048).

It is a super-2 number, since 2×81313569792000² (a number of 29 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81313569792001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 4279661567991 + ... + 4279661568009.

It is an arithmetic number, because the mean of its divisors is an integer number (66371000735).

Almost surely, 2^{81313569792000} is an apocalyptic number.

81313569792000 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 81313569792000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (200705906222640).

81313569792000 is an abundant number, since it is smaller than the sum of its proper divisors (320098242653280).

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

81313569792000 is an frugal number, since it uses more digits than its factorization.

81313569792000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111 (or 49 counting only the distinct ones).

The product of its (nonzero) digits is 2449440, while the sum is 54.

The spelling of 81313569792000 in words is "eighty-one trillion, three hundred thirteen billion, five hundred sixty-nine million, seven hundred ninety-two thousand".