81169793994 has 32 divisors (see below), whose sum is σ = 169417401984. Its totient is φ = 25877234240.

The previous prime is 81169793989. The next prime is 81169794023. The reversal of 81169793994 is 49939796118.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1376092 + ... + 1433864.

It is an arithmetic number, because the mean of its divisors is an integer number (5294293812).

Almost surely, 2^81169793994 is an apocalyptic number.

81169793994 is an abundant number, since it is smaller than the sum of its proper divisors (88247607990).

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

81169793994 is a wasteful number, since it uses less digits than its factorization.

81169793994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67982.

The product of its digits is 26453952, while the sum is 66.

The spelling of 81169793994 in words is "eighty-one billion, one hundred sixty-nine million, seven hundred ninety-three thousand, nine hundred ninety-four".