18007609 has 2 divisors, whose sum is σ = 18007610. Its totient is φ = 18007608.

The previous prime is 18007601. The next prime is 18007663. The reversal of 18007609 is 90670081.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17197609 + 810000 = 4147^2 + 900^2 .

It is a cyclic number.

It is not a de Polignac number, because 18007609 - 2³ = 18007601 is a prime.

It is not a weakly prime, because it can be changed into another prime (18007601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9003804 + 9003805.

It is an arithmetic number, because the mean of its divisors is an integer number (9003805).

Almost surely, 2^18007609 is an apocalyptic number.

It is an amenable number.

18007609 is a deficient number, since it is larger than the sum of its proper divisors (1).

18007609 is an equidigital number, since it uses as much as digits as its factorization.

18007609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 18007609 is about 4243.5373216221. The cubic root of 18007609 is about 262.1110624062. Note that the first 3 decimals are identical.

It can be divided in two parts, 1800 and 7609, that added together give a square (9409 = 97²).

The spelling of 18007609 in words is "eighteen million, seven thousand, six hundred nine".