18808589 has 2 divisors, whose sum is σ = 18808590. Its totient is φ = 18808588.

The previous prime is 18808571. The next prime is 18808619. The reversal of 18808589 is 98580881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13564489 + 5244100 = 3683^2 + 2290^2 .

It is a cyclic number.

It is not a de Polignac number, because 18808589 - 2⁸ = 18808333 is a prime.

It is a Sophie Germain 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 (18808529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9404294 + 9404295.

It is an arithmetic number, because the mean of its divisors is an integer number (9404295).

Almost surely, 2^18808589 is an apocalyptic number.

It is an amenable number.

18808589 is a deficient number, since it is larger than the sum of its proper divisors (1).

18808589 is an equidigital number, since it uses as much as digits as its factorization.

18808589 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 184320, while the sum is 47.

The square root of 18808589 is about 4336.8870172049. The cubic root of 18808589 is about 265.9410661456.

The spelling of 18808589 in words is "eighteen million, eight hundred eight thousand, five hundred eighty-nine".