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The numbers themselves are interesting: 6 is a perfect number (its proper factors have a sum of 6); 9 is a square number (3^2 = 9); and 12 is the least abundant number (its proper factors have a sum greater than 12).
So these are called the proper factors, or divisors--less than the number itself--of 30 and if we add them
PHOTO El Camino Real's Academic Decathlon team - a product of proper factors.