18685319 has 2 divisors, whose sum is σ = 18685320. Its totient is φ = 18685318.

The previous prime is 18685313. The next prime is 18685327. The reversal of 18685319 is 91358681.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18685319 - 2²⁰ = 17636743 is a prime.

It is a super-2 number, since 2×18685319² = 698282292263522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18685313) 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, 9342659 + 9342660.

It is an arithmetic number, because the mean of its divisors is an integer number (9342660).

Almost surely, 2^18685319 is an apocalyptic number.

18685319 is a deficient number, since it is larger than the sum of its proper divisors (1).

18685319 is an equidigital number, since it uses as much as digits as its factorization.

18685319 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 51840, while the sum is 41.

The square root of 18685319 is about 4322.6518481136. The cubic root of 18685319 is about 265.3588067104.

The spelling of 18685319 in words is "eighteen million, six hundred eighty-five thousand, three hundred nineteen".