18420306 has 16 divisors (see below), whose sum is σ = 37033824. Its totient is φ = 6107904.

The previous prime is 18420301. The next prime is 18420319. The reversal of 18420306 is 60302481.

It is a happy number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18420301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6796 + ... + 9111.

It is an arithmetic number, because the mean of its divisors is an integer number (2314614).

Almost surely, 2^18420306 is an apocalyptic number.

18420306 is an abundant number, since it is smaller than the sum of its proper divisors (18613518).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18420306 is a wasteful number, since it uses less digits than its factorization.

18420306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16105.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 18420306 is about 4291.8883955667. Note that the first 3 decimals coincide. The cubic root of 18420306 is about 264.0983047583.

Adding to 18420306 its reverse (60302481), we get a palindrome (78722787).

The spelling of 18420306 in words is "eighteen million, four hundred twenty thousand, three hundred six".