81115792 has 20 divisors (see below), whose sum is σ = 157489920. Its totient is φ = 40473248.

The previous prime is 81115781. The next prime is 81115829. The reversal of 81115792 is 29751118.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3009 + ... + 13087.

It is an arithmetic number, because the mean of its divisors is an integer number (7874496).

Almost surely, 2^81115792 is an apocalyptic number.

It is an amenable number.

81115792 is a deficient number, since it is larger than the sum of its proper divisors (76374128).

81115792 is a wasteful number, since it uses less digits than its factorization.

81115792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10590 (or 10584 counting only the distinct ones).

The product of its digits is 5040, while the sum is 34.

The square root of 81115792 is about 9006.4305915274. The cubic root of 81115792 is about 432.8809469536.

The spelling of 81115792 in words is "eighty-one million, one hundred fifteen thousand, seven hundred ninety-two".