18320805 has 24 divisors (see below), whose sum is σ = 31868928. Its totient is φ = 9736416.

The previous prime is 18320791. The next prime is 18320821. The reversal of 18320805 is 50802381.

It is a happy number.

It is not a de Polignac number, because 18320805 - 2⁵ = 18320773 is a prime.

It is a Curzon number.

It is a congruent 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 23 ways as a sum of consecutive naturals, for example, 16704 + ... + 17766.

It is an arithmetic number, because the mean of its divisors is an integer number (1327872).

Almost surely, 2^18320805 is an apocalyptic number.

18320805 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18320805 is a deficient number, since it is larger than the sum of its proper divisors (13548123).

18320805 is a wasteful number, since it uses less digits than its factorization.

18320805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1457 (or 1454 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 18320805 is about 4280.2809487229. The cubic root of 18320805 is about 263.6219191992.

The spelling of 18320805 in words is "eighteen million, three hundred twenty thousand, eight hundred five".