18320385 has 32 divisors (see below), whose sum is σ = 30228480. Its totient is φ = 9471168.

The previous prime is 18320371. The next prime is 18320387. The reversal of 18320385 is 58302381.

It is a happy number.

It is not a de Polignac number, because 18320385 - 2⁴ = 18320369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18320387) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 112314 + ... + 112476.

It is an arithmetic number, because the mean of its divisors is an integer number (944640).

Almost surely, 2^18320385 is an apocalyptic number.

18320385 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18320385 is a deficient number, since it is larger than the sum of its proper divisors (11908095).

18320385 is a wasteful number, since it uses less digits than its factorization.

18320385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 18320385 is about 4280.2318862417. The cubic root of 18320385 is about 263.6199046944.

The spelling of 18320385 in words is "eighteen million, three hundred twenty thousand, three hundred eighty-five".