81500236992 has 112 divisors (see below), whose sum is σ = 240090065920. Its totient is φ = 27110681856.

The previous prime is 81500236963. The next prime is 81500237023. The reversal of 81500236992 is 29963200518.

81500236992 is a `hidden beast` number, since 81 + 500 + 2 + 3 + 69 + 9 + 2 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 793113 + ... + 889959.

Almost surely, 2^81500236992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81500236992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120045032960).

81500236992 is an abundant number, since it is smaller than the sum of its proper divisors (158589828928).

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

81500236992 is a wasteful number, since it uses less digits than its factorization.

81500236992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97355 (or 97339 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The spelling of 81500236992 in words is "eighty-one billion, five hundred million, two hundred thirty-six thousand, nine hundred ninety-two".