18145289 has 2 divisors, whose sum is σ = 18145290. Its totient is φ = 18145288.

The previous prime is 18145279. The next prime is 18145297. The reversal of 18145289 is 98254181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15366400 + 2778889 = 3920^2 + 1667^2 .

It is an emirp because it is prime and its reverse (98254181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18145289 - 2⁸ = 18145033 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18145219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9072644 + 9072645.

It is an arithmetic number, because the mean of its divisors is an integer number (9072645).

Almost surely, 2^18145289 is an apocalyptic number.

It is an amenable number.

18145289 is a deficient number, since it is larger than the sum of its proper divisors (1).

18145289 is an equidigital number, since it uses as much as digits as its factorization.

18145289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23040, while the sum is 38.

The square root of 18145289 is about 4259.7287472326. The cubic root of 18145289 is about 262.7773709092. Note that the first 3 decimals are identical.

The spelling of 18145289 in words is "eighteen million, one hundred forty-five thousand, two hundred eighty-nine".