There are 38 willow trees planted on the back mountain. The number of pine trees is 5 times that of willow trees, and the number of apple trees is 9 times that of pine trees. How many apple trees are planted on the back mountain?
后山上种了38棵柳树，松树的棵数是柳树的5倍，苹果树的棵数是松数的9倍，后山种了多少棵苹果树？
<gadget id="calculator">38 * 5 * 9</gadget>
<output>1_710</output>

<result>1_710</result>