18412809 has 4 divisors (see below), whose sum is σ = 24550416. Its totient is φ = 12275204.

The previous prime is 18412777. The next prime is 18412817. The reversal of 18412809 is 90821481.

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 18412809 - 2⁵ = 18412777 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18412809.

It is not an unprimeable number, because it can be changed into a prime (18412859) 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, 3068799 + ... + 3068804.

It is an arithmetic number, because the mean of its divisors is an integer number (6137604).

Almost surely, 2^18412809 is an apocalyptic number.

It is an amenable number.

18412809 is a deficient number, since it is larger than the sum of its proper divisors (6137607).

18412809 is an equidigital number, since it uses as much as digits as its factorization.

18412809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6137606.

The product of its (nonzero) digits is 4608, while the sum is 33.

The square root of 18412809 is about 4291.0149149123. The cubic root of 18412809 is about 264.0624708682.

The spelling of 18412809 in words is "eighteen million, four hundred twelve thousand, eight hundred nine".