A book has page numbers on both sides of each page except the front and back covers. If the product of the page numbers on the two sides of the middle page is 2450, what is the sum of all page numbers in this book?
一本图书除封面和封底外的每页纸的两面都标有页码，若中间一页纸两面的页码之积是2450，则这本书的所有页码之和是多少．
<gadget id="calculator">2 * 5 * 5</gadget>
<output>50</output>

<gadget id="calculator">50 + 48</gadget>
<output>98</output>

<gadget id="calculator">1 + 98</gadget>
<output>99</output>

<gadget id="calculator">98 / 2</gadget>
<output>49</output>

<gadget id="calculator">99 * 49</gadget>
<output>4_851</output>

<result>4_851</result>