81198799 has 16 divisors (see below), whose sum is σ = 93559680. Its totient is φ = 69694560.

The previous prime is 81198791. The next prime is 81198823. The reversal of 81198799 is 99789118.

It is a cyclic number.

It is not a de Polignac number, because 81198799 - 2³ = 81198791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81198791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 92149 + ... + 93025.

It is an arithmetic number, because the mean of its divisors is an integer number (5847480).

Almost surely, 2^81198799 is an apocalyptic number.

81198799 is a deficient number, since it is larger than the sum of its proper divisors (12360881).

81198799 is a wasteful number, since it uses less digits than its factorization.

81198799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350.

The product of its digits is 326592, while the sum is 52.

The square root of 81198799 is about 9011.0376206073. The cubic root of 81198799 is about 433.0285544589.

The spelling of 81198799 in words is "eighty-one million, one hundred ninety-eight thousand, seven hundred ninety-nine".