18685099 has 2 divisors, whose sum is σ = 18685100. Its totient is φ = 18685098.

The previous prime is 18685087. The next prime is 18685133. The reversal of 18685099 is 99058681.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18685099 - 2⁵ = 18685067 is a prime.

It is not a weakly prime, because it can be changed into another prime (18685049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9342549 + 9342550.

It is an arithmetic number, because the mean of its divisors is an integer number (9342550).

Almost surely, 2^18685099 is an apocalyptic number.

18685099 is a deficient number, since it is larger than the sum of its proper divisors (1).

18685099 is an equidigital number, since it uses as much as digits as its factorization.

18685099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 155520, while the sum is 46.

The square root of 18685099 is about 4322.6264006967. The cubic root of 18685099 is about 265.3577652659.

The spelling of 18685099 in words is "eighteen million, six hundred eighty-five thousand, ninety-nine".