18308089 has 2 divisors, whose sum is σ = 18308090. Its totient is φ = 18308088.

The previous prime is 18308063. The next prime is 18308093. The reversal of 18308089 is 98080381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12902464 + 5405625 = 3592^2 + 2325^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18308089 is a prime.

It is a super-2 number, since 2×18308089² = 670372245663842, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18308029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9154044 + 9154045.

It is an arithmetic number, because the mean of its divisors is an integer number (9154045).

Almost surely, 2^18308089 is an apocalyptic number.

It is an amenable number.

18308089 is a deficient number, since it is larger than the sum of its proper divisors (1).

18308089 is an equidigital number, since it uses as much as digits as its factorization.

18308089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13824, while the sum is 37.

The square root of 18308089 is about 4278.7952743734. The cubic root of 18308089 is about 263.5609140162.

The spelling of 18308089 in words is "eighteen million, three hundred eight thousand, eighty-nine".