18806009 has 4 divisors (see below), whose sum is σ = 18817680. Its totient is φ = 18794340.

The previous prime is 18805951. The next prime is 18806077. The reversal of 18806009 is 90060881.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 18806009 - 2¹⁶ = 18740473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18806209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2939 + ... + 6800.

It is an arithmetic number, because the mean of its divisors is an integer number (4704420).

Almost surely, 2^18806009 is an apocalyptic number.

It is an amenable number.

18806009 is a deficient number, since it is larger than the sum of its proper divisors (11671).

18806009 is an equidigital number, since it uses as much as digits as its factorization.

18806009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11670.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 18806009 is about 4336.5895586278. The cubic root of 18806009 is about 265.9289057557.

The spelling of 18806009 in words is "eighteen million, eight hundred six thousand, nine".