#Use Exponents
If your language has an exponent operator you might be able to use it to generate, if not the number you want, at least a number you can perform a simple calculation or 2 on to arrive at your number. Even without an operator, you may still be able to save bytes with a built-in function or method.
##Example
The maximum safe integer in JavaScript is 9007199254740991, which is 16 digits long. In ES7, this can be calculated with the following 7 bytes:
2**53-1
The equivalent in ES6 and earlier, while the same length as the integer itself in this instance, demonstrates that using a more verbose method might not necessarily cost you any bytes.
Math.pow(2,53)-1
The above, though, may work out shorter if, for example, you already have Math aliased to a single character elsewhere in your code.