When a number is divided by 5, the quotient is 104, and the remainder is the largest. What is this number?
一个数除以5，商104，余数最大，这个数是多少．
<gadget id="calculator">5 * 104</gadget>
<output>520</output>

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">520 + 4</gadget>
<output>524</output>

<result>524</result>