What is 45 divisible by?

A number is divisible by 45 if it is divisible by both 5 and 9. This means that the last digit of the number must be either 0 or 5, and the sum of its digits must be divisible by 9. For example, 225 is divisible by 45 because it ends in 5 and its digits add up to 9. Other examples of numbers divisible by 45 include 720, 1350, and 5400.