81312768000 has 896 divisors, whose sum is σ = 320184109440. Its totient is φ = 20289945600.

The previous prime is 81312767989. The next prime is 81312768007. The reversal of 81312768000 is 86721318.

It is a super-2 number, since 2×81312768000² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81312768007) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 470015914 + ... + 470016086.

Almost surely, 2^81312768000 is an apocalyptic number.

81312768000 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 81312768000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160092054720).

81312768000 is an abundant number, since it is smaller than the sum of its proper divisors (238871341440).

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

81312768000 is a wasteful number, since it uses less digits than its factorization.

81312768000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240 (or 200 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The spelling of 81312768000 in words is "eighty-one billion, three hundred twelve million, seven hundred sixty-eight thousand".