81312960000 has 200 divisors, whose sum is σ = 270695056104. Its totient is φ = 21683200000.

The previous prime is 81312959999. The next prime is 81312960019. The reversal of 81312960000 is 6921318.

It is a tau number, because it is divible by the number of its divisors (200).

It is a super-2 number, since 2×81312960000² (a number of 23 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a self number, because there is not a number n which added to its sum of digits gives 81312960000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 917650 + ... + 1002350.

Almost surely, 2^81312960000 is an apocalyptic number.

81312960000 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 81312960000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135347528052).

81312960000 is an abundant number, since it is smaller than the sum of its proper divisors (189382096104).

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

81312960000 is an frugal number, since it uses more digits than its factorization.

81312960000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84742 (or 84711 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The spelling of 81312960000 in words is "eighty-one billion, three hundred twelve million, nine hundred sixty thousand".