Kant did not consider them sciences, but meta-disciplines that study a priori conditions of doing science. Indeed, both mathematics and philosophy permeate all empirical sciences to varying degrees, in fact to complementary degrees it seems. The more there is of mathematics in a field the less there is of philosophy (sadly).
Much is made about the difference with empirical sciences. However, if one believes in the Platonic realm and some means of accessing it directly (like Gödel did) then both mathematics and philosophy become "empirical" sciences of that. Husserl gave an account of ideal intuition that fulfills both conditions and is free of fantastic elements in Plato. So this distinction seems to rest on philosophical preferences.
One could also argue that proof standards in mathematics differ only in quantity rather than quality from soundness standards for theoretical arguments in empirical sciences. Another issue often brought up is experimental falsification. But from Kuhn we know that theories are not exactly falsified by individual experiments, they fall if they broadly fail. That isn't that different from mathematics and philosophy, although mathematical theories or philosophical systems are not "verified" or "falsified" fruitful ones are perpetuated (like Lebesgue measure theory or Kant's critical method), and unfruitful ones are abandoned and become historical curiosities (like classical invariant theory or Berkeley's solipsism). For mathematics the opposite sides are argued here and in the top answer to Is Mathematics considered a science? Argument about philosophy is mentioned here.
Not surprisingly, Husserl wanted philosophy to be a science, even a "rigorous" science. Ironically, it is analytic philosophy that comes closest to fulfilling his wish. However, even he distinguishes formal and empirical sciences (corresponding to his formal and regional ontologies), and places mathematics and philosophy with the former. On the other hand, most existensialists would have none of that. Even grouping mathematics with philosophy is controversial, in academia mathematics is usually put together with sciences, and philosophy with humanities. However, even some existentialists would probably claim that they study something more fundamental than "human culture" (Heidegger comes to mind).
Is there something to the question that does not reduce to an argument about words? Accepting Husserl's formal/empirical terminology can the underlying common of "science" be identified without including "pseudo-sciences" (or should some of them be included)? And if mathematics and philosophy are (are not) sciences should they be (not be)? In case of the negative answer, how is the role of mathematics and philosophy similar/different to that of "sciences"?