18016809 has 4 divisors (see below), whose sum is σ = 24022416. Its totient is φ = 12011204.

The previous prime is 18016799. The next prime is 18016829. The reversal of 18016809 is 90861081.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18016809 - 2⁴ = 18016793 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18016809.

It is not an unprimeable number, because it can be changed into a prime (18016829) 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 in 3 ways as a sum of consecutive naturals, for example, 3002799 + ... + 3002804.

It is an arithmetic number, because the mean of its divisors is an integer number (6005604).

Almost surely, 2^18016809 is an apocalyptic number.

It is an amenable number.

18016809 is a deficient number, since it is larger than the sum of its proper divisors (6005607).

18016809 is an equidigital number, since it uses as much as digits as its factorization.

18016809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6005606.

The product of its (nonzero) digits is 3456, while the sum is 33.

The square root of 18016809 is about 4244.6211845111. The cubic root of 18016809 is about 262.1556918964.

The spelling of 18016809 in words is "eighteen million, sixteen thousand, eight hundred nine".