18264989 has 2 divisors, whose sum is σ = 18264990. Its totient is φ = 18264988.

The previous prime is 18264979. The next prime is 18264997. The reversal of 18264989 is 98946281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17347225 + 917764 = 4165^2 + 958^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18264989 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18264929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9132494 + 9132495.

It is an arithmetic number, because the mean of its divisors is an integer number (9132495).

Almost surely, 2^18264989 is an apocalyptic number.

It is an amenable number.

18264989 is a deficient number, since it is larger than the sum of its proper divisors (1).

18264989 is an equidigital number, since it uses as much as digits as its factorization.

18264989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 47.

The square root of 18264989 is about 4273.7558423476. The cubic root of 18264989 is about 263.3539308071.

The spelling of 18264989 in words is "eighteen million, two hundred sixty-four thousand, nine hundred eighty-nine".