18219169 has 2 divisors, whose sum is σ = 18219170. Its totient is φ = 18219168.

The previous prime is 18219161. The next prime is 18219191. The reversal of 18219169 is 96191281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17430625 + 788544 = 4175^2 + 888^2 .

It is a cyclic number.

It is not a de Polignac number, because 18219169 - 2³ = 18219161 is a prime.

It is a super-2 number, since 2×18219169² = 663876238101122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18219161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9109584 + 9109585.

It is an arithmetic number, because the mean of its divisors is an integer number (9109585).

Almost surely, 2^18219169 is an apocalyptic number.

It is an amenable number.

18219169 is a deficient number, since it is larger than the sum of its proper divisors (1).

18219169 is an equidigital number, since it uses as much as digits as its factorization.

18219169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776, while the sum is 37.

The square root of 18219169 is about 4268.3918517400. The cubic root of 18219169 is about 263.1335276884.

The spelling of 18219169 in words is "eighteen million, two hundred nineteen thousand, one hundred sixty-nine".