18169009 has 2 divisors, whose sum is σ = 18169010. Its totient is φ = 18169008.

The previous prime is 18169003. The next prime is 18169031. The reversal of 18169009 is 90096181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17247409 + 921600 = 4153^2 + 960^2 .

It is a cyclic number.

It is not a de Polignac number, because 18169009 - 2⁵ = 18168977 is a prime.

It is a super-2 number, since 2×18169009² = 660225776084162, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18169003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9084504 + 9084505.

It is an arithmetic number, because the mean of its divisors is an integer number (9084505).

Almost surely, 2^18169009 is an apocalyptic number.

It is an amenable number.

18169009 is a deficient number, since it is larger than the sum of its proper divisors (1).

18169009 is an equidigital number, since it uses as much as digits as its factorization.

18169009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 18169009 is about 4262.5120527689. The cubic root of 18169009 is about 262.8918242198.

The spelling of 18169009 in words is "eighteen million, one hundred sixty-nine thousand, nine".