18089917 has 2 divisors, whose sum is σ = 18089918. Its totient is φ = 18089916.

The previous prime is 18089909. The next prime is 18089923. The reversal of 18089917 is 71998081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17189316 + 900601 = 4146^2 + 949^2 .

It is a cyclic number.

It is not a de Polignac number, because 18089917 - 2³ = 18089909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18089927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9044958 + 9044959.

It is an arithmetic number, because the mean of its divisors is an integer number (9044959).

Almost surely, 2^18089917 is an apocalyptic number.

It is an amenable number.

18089917 is a deficient number, since it is larger than the sum of its proper divisors (1).

18089917 is an equidigital number, since it uses as much as digits as its factorization.

18089917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 18089917 is about 4253.2243063351. The cubic root of 18089917 is about 262.5098022039.

The spelling of 18089917 in words is "eighteen million, eighty-nine thousand, nine hundred seventeen".