According to Wolfram alpha, you could put in another Earth and two more Mercury's and still have 1600km leftover. https://www.wolframalpha.com/input?i=%28earth

According to Wolfram alpha, you could put in another Earth and two more Mercury's and still have 1600km leftover. https://www.wolframalpha.com/input?i=%28earth+to+moon+distance%29+-+%28%283*diameter+of+mercury%29+%2B+diameter+of+venus+%2B+diameter+of+earth+%2B+diameter+of+mars+%2B+diameter+of+jupiter+%2B+diameter+of+saturn+%2B+diameter+of+uranus+%2B+diameter+of+neptune%29 https://www.wolframalpha.com/input?i=%28earth+to+moon+distan...