18168149 has 2 divisors, whose sum is σ = 18168150. Its totient is φ = 18168148.

The previous prime is 18168113. The next prime is 18168151. The reversal of 18168149 is 94186181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14577124 + 3591025 = 3818^2 + 1895^2 .

It is an emirp because it is prime and its reverse (94186181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18168149 - 2¹² = 18164053 is a prime.

It is a Sophie Germain prime.

Together with 18168151, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18168109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9084074 + 9084075.

It is an arithmetic number, because the mean of its divisors is an integer number (9084075).

Almost surely, 2^18168149 is an apocalyptic number.

It is an amenable number.

18168149 is a deficient number, since it is larger than the sum of its proper divisors (1).

18168149 is an equidigital number, since it uses as much as digits as its factorization.

18168149 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 38.

The square root of 18168149 is about 4262.4111720950. The cubic root of 18168149 is about 262.8876763045.

The spelling of 18168149 in words is "eighteen million, one hundred sixty-eight thousand, one hundred forty-nine".