Presumably, that’s as big as a set of numbers can get. But Cantor showed that, paradoxically, though the number of fractions is the same as the number of integers, there are demonstrably more ...

So, if we have the number in cell ‘B2’ then, B2^(1/2) gives square root of a number available in cell B2. These are 3 different ways to find the square root of a number in Excel easily.