18320899 has 2 divisors, whose sum is σ = 18320900. Its totient is φ = 18320898.

The previous prime is 18320879. The next prime is 18320909. The reversal of 18320899 is 99802381.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18320899 - 2⁵ = 18320867 is a prime.

It is not a weakly prime, because it can be changed into another prime (18320879) 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 as a sum of consecutive naturals, namely, 9160449 + 9160450.

It is an arithmetic number, because the mean of its divisors is an integer number (9160450).

Almost surely, 2^18320899 is an apocalyptic number.

18320899 is a deficient number, since it is larger than the sum of its proper divisors (1).

18320899 is an equidigital number, since it uses as much as digits as its factorization.

18320899 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 18320899 is about 4280.2919292964. The cubic root of 18320899 is about 263.6223700604.

The spelling of 18320899 in words is "eighteen million, three hundred twenty thousand, eight hundred ninety-nine".