81816099 has 8 divisors (see below), whose sum is σ = 112607232. Its totient is φ = 52784520.

The previous prime is 81816089. The next prime is 81816103. The reversal of 81816099 is 99061818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81816099 - 2²³ = 73427491 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81816099.

It is not an unprimeable number, because it can be changed into a prime (81816079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 439779 + ... + 439964.

It is an arithmetic number, because the mean of its divisors is an integer number (14075904).

Almost surely, 2^81816099 is an apocalyptic number.

81816099 is a deficient number, since it is larger than the sum of its proper divisors (30791133).

81816099 is a wasteful number, since it uses less digits than its factorization.

81816099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 879777.

The product of its (nonzero) digits is 31104, while the sum is 42.

The square root of 81816099 is about 9045.2252044933. The cubic root of 81816099 is about 434.1231272332.

The spelling of 81816099 in words is "eighty-one million, eight hundred sixteen thousand, ninety-nine".