81192538 has 16 divisors (see below), whose sum is σ = 139313664. Its totient is φ = 34765200.

The previous prime is 81192523. The next prime is 81192577. The reversal of 81192538 is 83529118.

It is a junction number, because it is equal to n+sod(n) for n = 81192497 and 81192506.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20088 + ... + 23788.

It is an arithmetic number, because the mean of its divisors is an integer number (8707104).

Almost surely, 2^81192538 is an apocalyptic number.

81192538 is a deficient number, since it is larger than the sum of its proper divisors (58121126).

81192538 is a wasteful number, since it uses less digits than its factorization.

81192538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5277.

The product of its digits is 17280, while the sum is 37.

The square root of 81192538 is about 9010.6902066379. The cubic root of 81192538 is about 433.0174243211.

The spelling of 81192538 in words is "eighty-one million, one hundred ninety-two thousand, five hundred thirty-eight".