See: Types of Functions
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Is there any other type of function left outside this classification?
Continuous, discontinuous, differentiable, piecewise continuous, open, closed, compact supported, bounded, with bounded variation and many more besides all functions that have a domain or codomain other than the reals.
For the second, It is the Primitive of an exponetial function, but as far as I know, it cannot be expressed by elementary functions. So I think it is NOT exponential
– Tito Eliatron Dec 27 '18 at 18:44