With InteractiveCalculator you have access to the Excel text functions your're used to. Notice that you need to use the TRIM functions on the fields to turn them into Text, as they're normally assigned a number value inside formulas.
Returns the left 2 characters of the NumberField
Returns the right 2 characters of the NumberField
Returns the 2 characters of the NumberField starting from the 3rd character
Returns the number of characters of the NumberField
Returns the text in the Short/Long Text Answer field or a Formula field that outputs a text instead of a number
Returns the title (label) of the question (must have the outer quotes to be evaluated as a string text)