18682809 has 4 divisors (see below), whose sum is σ = 24910416. Its totient is φ = 12455204.

The previous prime is 18682799. The next prime is 18682849. The reversal of 18682809 is 90828681.

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, and also an emirpimes, since its reverse is a distinct semiprime: 90828681 = 3 ⋅30276227.

It is a cyclic number.

It is not a de Polignac number, because 18682809 - 2¹² = 18678713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18682849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3113799 + ... + 3113804.

It is an arithmetic number, because the mean of its divisors is an integer number (6227604).

Almost surely, 2^18682809 is an apocalyptic number.

It is an amenable number.

18682809 is a deficient number, since it is larger than the sum of its proper divisors (6227607).

18682809 is an equidigital number, since it uses as much as digits as its factorization.

18682809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6227606.

The product of its (nonzero) digits is 55296, while the sum is 42.

The square root of 18682809 is about 4322.3615073244. The cubic root of 18682809 is about 265.3469242903.

It can be divided in two parts, 18682 and 809, that added together give a palindrome (19491).

The spelling of 18682809 in words is "eighteen million, six hundred eighty-two thousand, eight hundred nine".