18409199 has 2 divisors, whose sum is σ = 18409200. Its totient is φ = 18409198.

The previous prime is 18409163. The next prime is 18409201. The reversal of 18409199 is 99190481.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18409199 is a prime.

Together with 18409201, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18409109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9204599 + 9204600.

It is an arithmetic number, because the mean of its divisors is an integer number (9204600).

Almost surely, 2^18409199 is an apocalyptic number.

18409199 is a deficient number, since it is larger than the sum of its proper divisors (1).

18409199 is an equidigital number, since it uses as much as digits as its factorization.

18409199 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 18409199 is about 4290.5942478869. The cubic root of 18409199 is about 264.0452124509.

The spelling of 18409199 in words is "eighteen million, four hundred nine thousand, one hundred ninety-nine".