A cube iron box with a side length of 20 cm, how many square centimeters of iron sheet is needed to make this iron box?
一个正方体铁盒，棱长20厘米，做这个铁盒至少需要多少平方厘米的铁皮？
<gadget id="calculator">20 * 20 * 6</gadget>
<output>2_400</output>

<result>2_400</result>