A circular wall clock with a bottom circumference of 62.8 cm is exactly placed in a rectangular packing box. The thickness of the wall clock is calculated as 4 cm. How much cardboard is needed to make this packing box? (the interface part is not counted)
一个长方形的包装盒中恰好放一个底面周长是62.8厘米的圆形挂钟，挂钟的厚度按4厘米计算，做这个包装盒需要多少硬纸板？(接口部分不算)
<gadget id="calculator">62.8 / 3.14</gadget>
<output>20</output>

<gadget id="calculator">20 * 20 * 2</gadget>
<output>800</output>

<gadget id="calculator">20 * 4 * 4</gadget>
<output>320</output>

<gadget id="calculator">800 + 320</gadget>
<output>1_120</output>

<result>1_120</result>