What is the highest prime factor of 420?

To find the highest prime factor of 420, we first need to factorize 420 into its prime factors. 420 can be expressed as 2^2 * 3 * 5 * 7. The highest prime factor is 7. Prime factors are numbers that can only be divided by 1 and themselves without leaving a remainder, and the highest prime factor is the largest Prime number that can divide the original number.