18436919 has 2 divisors, whose sum is σ = 18436920. Its totient is φ = 18436918.

The previous prime is 18436903. The next prime is 18436931. The reversal of 18436919 is 91963481.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18436919 - 2⁴ = 18436903 is a prime.

It is a super-2 number, since 2×18436919² = 679839964425122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18436819) 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, 9218459 + 9218460.

It is an arithmetic number, because the mean of its divisors is an integer number (9218460).

Almost surely, 2^18436919 is an apocalyptic number.

18436919 is a deficient number, since it is larger than the sum of its proper divisors (1).

18436919 is an equidigital number, since it uses as much as digits as its factorization.

18436919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 41.

The square root of 18436919 is about 4293.8233545408. The cubic root of 18436919 is about 264.1776763460.

The spelling of 18436919 in words is "eighteen million, four hundred thirty-six thousand, nine hundred nineteen".