Our sun is so big that 1 million earths could fit inside of it. On the other hand, the largest star known to man is called VY Canis Majoris which could house 9,261,000,000 Suns.
If VY Canis Majoris were put in our sun's place it would extend past Saturn. VY Canis Majoris can also fit 7x10^15 Earths inside of it (that's 7 with 15 zeros after it.)
(Sources: 1, 2, and some math)