18008161 has 2 divisors, whose sum is σ = 18008162. Its totient is φ = 18008160.

The previous prime is 18008153. The next prime is 18008167. The reversal of 18008161 is 16180081.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14107536 + 3900625 = 3756^2 + 1975^2 .

It is a cyclic number.

It is not a de Polignac number, because 18008161 - 2³ = 18008153 is a prime.

It is equal to p_1151845 and since 18008161 and 1151845 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (18008167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9004080 + 9004081.

It is an arithmetic number, because the mean of its divisors is an integer number (9004081).

Almost surely, 2^18008161 is an apocalyptic number.

It is an amenable number.

18008161 is a deficient number, since it is larger than the sum of its proper divisors (1).

18008161 is an equidigital number, since it uses as much as digits as its factorization.

18008161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 25.

The square root of 18008161 is about 4243.6023612021. The cubic root of 18008161 is about 262.1137406042.

The spelling of 18008161 in words is "eighteen million, eight thousand, one hundred sixty-one".