9. Li Hua, when buying a certain product, mistakenly read a "7" in the unit price as a "1", and was preparing to pay 489 yuan, but actually should have paid 147 yuan. It is known that the unit price and the quantity of the product purchased are both integers, then the actual unit price of this product is $\qquad$ yuan, and Li Hua bought $\qquad$ pieces.
21 yuan, 7 pieces