Use rectangular paper with a length of 20 cm and a width of 16 cm to assemble a square. What is the minimum area of the square in square centimeters?
用长20厘米，宽16厘米的长方形纸拼正方形，正方形的面积最小是多少平方厘米？
<gadget id="calculator">2 * 2 * 2 * 2 * 5</gadget>
<output>80</output>

<gadget id="calculator">80 * 80</gadget>
<output>6_400</output>

<result>6_400</result>