Why does a number have to be encapsulated in an expression containing that number before methods can be applied to it?

Question

1.toString() gives us Uncaught SyntaxError: Invalid or unexpected token.

One the other hand, (1).toString() returns '1'.

Considering that typeof 1 === typeof (1) (both are of type number), why is this the case?

Answer 1

In JS number literals might be both integers and floats, so probably after finding . after the number translator expects to parse a float, like 1.123.