18320225 has 48 divisors (see below), whose sum is σ = 29331456. Its totient is φ = 11016000.

The previous prime is 18320221. The next prime is 18320227. The reversal of 18320225 is 52202381.

It is not a de Polignac number, because 18320225 - 2² = 18320221 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18320225.

It is not an unprimeable number, because it can be changed into a prime (18320221) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 59522 + ... + 59828.

It is an arithmetic number, because the mean of its divisors is an integer number (611072).

Almost surely, 2^18320225 is an apocalyptic number.

It is an amenable number.

18320225 is a deficient number, since it is larger than the sum of its proper divisors (11011231).

18320225 is a wasteful number, since it uses less digits than its factorization.

18320225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366 (or 361 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 18320225 is about 4280.2131956247. The cubic root of 18320225 is about 263.6191372559.

The spelling of 18320225 in words is "eighteen million, three hundred twenty thousand, two hundred twenty-five".