81198892 has 24 divisors (see below), whose sum is σ = 145575360. Its totient is φ = 39611520.

The previous prime is 81198877. The next prime is 81198899. The reversal of 81198892 is 29889118.

It is not an unprimeable number, because it can be changed into a prime (81198899) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 97534 + ... + 98362.

It is an arithmetic number, because the mean of its divisors is an integer number (6065640).

Almost surely, 2^81198892 is an apocalyptic number.

It is an amenable number.

81198892 is a deficient number, since it is larger than the sum of its proper divisors (64376468).

81198892 is a wasteful number, since it uses less digits than its factorization.

81198892 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1401 (or 1399 counting only the distinct ones).

The product of its digits is 82944, while the sum is 46.

The square root of 81198892 is about 9011.0427809438. The cubic root of 81198892 is about 433.0287197801.

The spelling of 81198892 in words is "eighty-one million, one hundred ninety-eight thousand, eight hundred ninety-two".