Solution: The GCF of 5 and 144 is 1MethodsHow to find the GCF of 5 and 144 using Prime FactorizationOne way to find the GCF of 5 and 144 is to compare the prime factorization of each number. To find the prime factorization, you can follow the instructions for each number here:What are the Factors of 5?What are the Factors of 144?Here is the prime factorization of 5:515^151And this is the prime factorization of 144:24×322^4 × 3^224×32When you compare the prime factorization of these two numbers, you can see that there are no matching prime factors. When this is the case, it means that there are no common factors between these two numbers. As a result, the GCF of 5 and 144 is 1.Thus, the GCF of 5 and 144 is: 1How to Find the GCF of 5 and 144 by Listing All Common FactorsThe first step to this method of finding the Greatest Common Factor of 5 and 144 is to find and list all the factors of each number. Again, you can see how this is done by looking at the “Factors of” articles that are linked to above.Let’s take a look at the factors for each of these numbers, 5 and 144:Factors of 5: 1, 5Factors of 144: 1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 24, 36, 48, 72, 144When you compare the two lists of factors, you can see that the only common factor is 1. So, in this case, the GCF of 5 and 144 is 1.Find the GCF of Other Number PairsWant more practice? Try some of these other GCF problems:What is the GCF of 109 and 3?What is the GCF of 28 and 72?What is the GCF of 21 and 79?What is the GCF of 42 and 27?What is the GCF of 136 and 33?