81120753792 has 96 divisors (see below), whose sum is σ = 251389882380. Its totient is φ = 24960227328.

The previous prime is 81120753767. The next prime is 81120753809. The reversal of 81120753792 is 29735702118.

81120753792 is a `hidden beast` number, since 8 + 1 + 1 + 20 + 7 + 537 + 92 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 81033592896 + 87160896 = 284664^2 + 9336^2 .

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2693383 + ... + 2723334.

Almost surely, 2^81120753792 is an apocalyptic number.

It is an amenable number.

81120753792 is an abundant number, since it is smaller than the sum of its proper divisors (170269128588).

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

81120753792 is a wasteful number, since it uses less digits than its factorization.

81120753792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5416750 (or 5416735 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 45.

The spelling of 81120753792 in words is "eighty-one billion, one hundred twenty million, seven hundred fifty-three thousand, seven hundred ninety-two".