81792695920 has 80 divisors (see below), whose sum is σ = 208267607520. Its totient is φ = 29688486912.

The previous prime is 81792695909. The next prime is 81792695947. The reversal of 81792695920 is 2959629718.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

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, 605139 + ... + 727858.

It is an arithmetic number, because the mean of its divisors is an integer number (2603345094).

Almost surely, 2^81792695920 is an apocalyptic number.

81792695920 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81792695920 is an abundant number, since it is smaller than the sum of its proper divisors (126474911600).

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

81792695920 is a wasteful number, since it uses less digits than its factorization.

81792695920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1333082 (or 1333076 counting only the distinct ones).

The product of its (nonzero) digits is 4898880, while the sum is 58.

The spelling of 81792695920 in words is "eighty-one billion, seven hundred ninety-two million, six hundred ninety-five thousand, nine hundred twenty".