C programm
If their GCF is 1, their LCM is their product. If their GCF is greater than 1, their LCM is less than their product.
Given any number, there is an even number that exists greater than it. That even number is a product: of 2 and some number. Therefore, the number that you started with is less than the product of a pair of numbers.
By finding out whether they have any factors in common. If the only factor they have in common is 1, the LCM will be their product. If they have more factors in common, their LCM will be less than their product.
Comparison
Compare numbers.
If none of the prime factors are in common, the LCM will be the product of the two.
If the two numbers have no common factors other than 1, the LCM will be their product. If there are other common factors, the LCM will be less.
If the prime factorizations have no factors in common, the LCM is the product of them.
If they have no common factors other than 1.
If the two numbers have no common prime factors, the LCM will be the product of the numbers.
A product is a binary operator. That means a product is the result of combining TWO numbers. You cannot have a product of just one number - whether it is a fraction or not is irrelevant.
You get another number whose magnitude will be greater than the original number. Whether it is bigger or smaller will depend on whether the whole number was positive or negative.