18243185 has 8 divisors (see below), whose sum is σ = 22004136. Its totient is φ = 14519680.

The previous prime is 18243161. The next prime is 18243241. The reversal of 18243185 is 58134281.

It can be written as a sum of positive squares in 4 ways, for example, as 12902464 + 5340721 = 3592^2 + 2311^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18243185 - 2²⁰ = 17194609 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 8276 + ... + 10245.

It is an arithmetic number, because the mean of its divisors is an integer number (2750517).

Almost surely, 2^18243185 is an apocalyptic number.

It is an amenable number.

18243185 is a deficient number, since it is larger than the sum of its proper divisors (3760951).

18243185 is a wasteful number, since it uses less digits than its factorization.

18243185 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18723.

The product of its digits is 7680, while the sum is 32.

The square root of 18243185 is about 4271.2041627625. The cubic root of 18243185 is about 263.2490953475.

The spelling of 18243185 in words is "eighteen million, two hundred forty-three thousand, one hundred eighty-five".