Number of ways to express a natural number N as a product of K natural numbers where each number is greater than or equal to a natural number M?

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I want to know the number of ways to express a natural number N as a product of K natural numbers where each number is greater than or equal to a natural number M? Or a simpler version of the problem can be to determine if it is even possible or not, keeping aside the number of ways of doing it. For example, 4 can be expressed as a product of two natural numbers where each number is greater than or equal to 2, i.e., 4 = 2 x 2, in one way. I tried searching for a solution to this problem but I couldn't find one. I know how to solve problems like xyz = 120 but there are no restrictions on what values x, y or z, like the one the above problem has. So what should be done in order to solve the above problem?