18949209 has 16 divisors (see below), whose sum is σ = 26308800. Its totient is φ = 12117056.

The previous prime is 18949181. The next prime is 18949211. The reversal of 18949209 is 90294981.

It is a cyclic number.

It is not a de Polignac number, because 18949209 - 2⁷ = 18949081 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (18949009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14422 + ... + 15680.

It is an arithmetic number, because the mean of its divisors is an integer number (1644300).

Almost surely, 2^18949209 is an apocalyptic number.

It is an amenable number.

18949209 is a deficient number, since it is larger than the sum of its proper divisors (7359591).

18949209 is a wasteful number, since it uses less digits than its factorization.

18949209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1464.

The product of its (nonzero) digits is 46656, while the sum is 42.

The square root of 18949209 is about 4353.0689174420. The cubic root of 18949209 is about 266.6021793717.

The spelling of 18949209 in words is "eighteen million, nine hundred forty-nine thousand, two hundred nine".