The length of 3.8 billion pairs of disposable chopsticks connected end to end can travel from the earth to the moon once. The length of the end-to-end disposable chopsticks produced in my country every year can travel from the earth to the moon 21 times. How many billion pairs of disposable chopsticks are produced in my country every year?
38亿双一次性筷子首尾相接的长度可以从地球往返月球1次．我国每年生产的一次性筷子首尾相接的长度可以从地球往返月球21次．我国每年生产多少亿双一次性筷子？
<gadget id="calculator">38 * 21</gadget>
<output>798</output>

<result>798</result>