Use 1, 2, 3, 4, 5 to form a three-digit number and a two-digit number. When multiplying the three-digit number and the two-digit number, what is the largest product?
用1、2、3、4、5五个数码组成一个三位数和一个两位数，这个三位数和这个两位数相乘，乘积最大的是多少．
<gadget id="calculator">431 * 52</gadget>
<output>22_412</output>

<result>22_412</result>