How many square centimeters of cardboard are needed to make a cube with a side length of 15 centimeters?
做一个棱长是15厘米的正方体纸盒，需要多少平方厘米的纸板？
<gadget id="calculator">15 * 15 * 6</gadget>
<output>1_350</output>

<result>1_350</result>