Print all unique combination of factors of a given number

Question

What is the most efficient algorithm to print all unique combinations of factors of a positive integer. For example if the given number is 24 then the output should be

Answer 1

I came up with this, seems easy to read and understand. Hope it helps!

def getFactors(num):

    results = []

    if num == 1 or 0:
        return [num]

    for i in range(num/2, 1, -1):

        if (num % i == 0):
            divisor = num / i

            if(divisor <= i):
                results.append([i, divisor])

            innerResults = getFactors(divisor)

            for innerResult in innerResults:
                if innerResult[0] <= i:
                    results.append([i] + innerResult)

    return results