An **ugly number** is a positive integer whose prime factors are limited to `2`, `3`, and `5`.
Given an integer `n`, return `true` if `n` is an ugly number, and `false` otherwise.
Note that `1` is considered ugly (it has no prime factors at all).
Example 1
Input:n = 6
Output:true
Explanation:6 = 2 x 3, only primes 2 and 3 appear.
Example 2
Input:n = 1
Output:true
Explanation:1 has no prime factors, so none outside {2, 3, 5}.
Example 3
Input:n = 14
Output:false
Explanation:14 = 2 x 7 includes the prime factor 7.