18321384 has 16 divisors (see below), whose sum is σ = 45803520. Its totient is φ = 6107120.

The previous prime is 18321371. The next prime is 18321389. The reversal of 18321384 is 48312381.

It is a super-2 number, since 2×18321384² = 671346223350912, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (18321389) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 381672 + ... + 381719.

It is an arithmetic number, because the mean of its divisors is an integer number (2862720).

Almost surely, 2^18321384 is an apocalyptic number.

It is an amenable number.

18321384 is an abundant number, since it is smaller than the sum of its proper divisors (27482136).

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

18321384 is a wasteful number, since it uses less digits than its factorization.

18321384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 763400 (or 763396 counting only the distinct ones).

The product of its digits is 4608, while the sum is 30.

The square root of 18321384 is about 4280.3485839357. The cubic root of 18321384 is about 263.6246962876.

The spelling of 18321384 in words is "eighteen million, three hundred twenty-one thousand, three hundred eighty-four".