Question: what is the greatest common factor of m and n?
Answer: Let m = 2 × 34 × 72 and n = 22 × 32 × 53 × 7. The powers of primes that are common are 2, 32, and 7. So the GCF of m and n is 2 × 32 × 7. The GCF is also called the greatest common divisor (GCD) because when a number is a factor, it is also a divisor.