18408 has 32 divisors (see below), whose sum is σ = 50400. Its totient is φ = 5568.

The previous prime is 18401. The next prime is 18413. The reversal of 18408 is 80481.

18408 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (18401) by changing a digit.

18408 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 283 + ... + 341.

It is an arithmetic number, because the mean of its divisors is an integer number (1575).

2¹⁸⁴⁰⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25200).

18408 is an abundant number, since it is smaller than the sum of its proper divisors (31992).

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

18408 is a wasteful number, since it uses less digits than its factorization.

18408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

The square root of 18408 is about 135.6760848492. The cubic root of 18408 is about 26.4039479862.

Adding to 18408 its reverse (80481), we get a palindrome (98889).

The spelling of 18408 in words is "eighteen thousand, four hundred eight".