18225909 has 12 divisors (see below), whose sum is σ = 28351596. Its totient is φ = 11215872.

The previous prime is 18225869. The next prime is 18225917. The reversal of 18225909 is 90952281.

It can be written as a sum of positive squares in 2 ways, for example, as 5049009 + 13176900 = 2247^2 + 3630^2 .

It is not a de Polignac number, because 18225909 - 2⁸ = 18225653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18225919) 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 11 ways as a sum of consecutive naturals, for example, 77772 + ... + 78005.

It is an arithmetic number, because the mean of its divisors is an integer number (2362633).

Almost surely, 2^18225909 is an apocalyptic number.

It is an amenable number.

18225909 is a deficient number, since it is larger than the sum of its proper divisors (10125687).

18225909 is a wasteful number, since it uses less digits than its factorization.

18225909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155796 (or 155793 counting only the distinct ones).

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

The square root of 18225909 is about 4269.1813032477. The cubic root of 18225909 is about 263.1659715633.

The spelling of 18225909 in words is "eighteen million, two hundred twenty-five thousand, nine hundred nine".