18006559 has 2 divisors, whose sum is σ = 18006560. Its totient is φ = 18006558.

The previous prime is 18006557. The next prime is 18006613. The reversal of 18006559 is 95560081.

It is a weak prime.

It is an emirp because it is prime and its reverse (95560081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18006559 - 2¹ = 18006557 is a prime.

Together with 18006557, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18006557) 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, 9003279 + 9003280.

It is an arithmetic number, because the mean of its divisors is an integer number (9003280).

Almost surely, 2^18006559 is an apocalyptic number.

18006559 is a deficient number, since it is larger than the sum of its proper divisors (1).

18006559 is an equidigital number, since it uses as much as digits as its factorization.

18006559 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10800, while the sum is 34.

The square root of 18006559 is about 4243.4136022782. The cubic root of 18006559 is about 262.1059678567.

The spelling of 18006559 in words is "eighteen million, six thousand, five hundred fifty-nine".