18450909 has 10 divisors (see below), whose sum is σ = 27562590. Its totient is φ = 12300552.

The previous prime is 18450907. The next prime is 18450947. The reversal of 18450909 is 90905481.

It can be written as a sum of positive squares in only one way, i.e., 17892900 + 558009 = 4230^2 + 747^2 .

It is not a de Polignac number, because 18450909 - 2¹ = 18450907 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18450907) 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 9 ways as a sum of consecutive naturals, for example, 113814 + ... + 113975.

It is an arithmetic number, because the mean of its divisors is an integer number (2756259).

Almost surely, 2^18450909 is an apocalyptic number.

It is an amenable number.

18450909 is a deficient number, since it is larger than the sum of its proper divisors (9111681).

18450909 is an equidigital number, since it uses as much as digits as its factorization.

18450909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227801 (or 227792 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 18450909 is about 4295.4521298695. The cubic root of 18450909 is about 264.2444791070.

The spelling of 18450909 in words is "eighteen million, four hundred fifty thousand, nine hundred nine".