2x10^30 / 3x10^-27

2x10^30  /  3x10^-27

I expect that you mean

(2x10^30 ) / ( 3x10^-27)

$= (2/3)     *     10^{30--27}\\ =0.\dot6*10^{57}\\ =6.\dot6*10^{-1}*10^{57}\\ =6.\dot6*10^{56}\\$