There are 20 bookshelves in the school library, each shelf has 5 floors, and each floor can hold 64 books. How many books can be placed in the school library?
学校图书室有20个书架，每个书架有5层，每层可放图书64本，学校图书室一共可放图书多少本？
<gadget id="calculator">5 * 64 * 20</gadget>
<output>6_400</output>

<result>6_400</result>