Finding Factors of a Number, GCF, and Prime and Composite Numbers! Use this product to provide practice for your students in finding factors of a number, then finding the GCF of a pair or set of numbers. It also provides practice in identifying prime and composite numbers. The lessons in the companion material for this product (sold separately) provide step-by-step instructions for finding factors of a number, then identifying the GCF ( Greatest Common Factor) of a pair or set of numbers. Th