About 1.3 million Earths can fit inside the Sun. This estimate comes from comparing their volumes: the Sun's volume is approximately 1.41×10181.41\times 10^{18}1.41×1018 cubic kilometers, while Earth's volume is about 1.09×10121.09\times 10^{12}1.09×1012 cubic kilometers. Dividing the Sun's volume by Earth's volume gives roughly 1.3 million Earths fitting inside the Sun
. This huge difference is because the Sun's radius is about 109 times that of Earth, and since volume scales with the cube of the radius, the Sun's volume is vastly greater despite the linear size difference
