What is the smallest factor of all numbers?
A number a has 7 as its smallest prime factor, and another number b has 3 as its smallest prime factor. What is the smallest prime factor of the number a−b?
A number a has 3 as its smallest prime factor, and another number b has 5 as its smallest prime factor. What is the smallest prime factor of the number a+b?
What is the smallest number with exactly five factors?