If you don’t have the Numpad on your keyboard, Blender has the functionalities of all those keys in the pie menu of the Tilde key:

So in essence you could do without the Numpad and just use the pie menu. In fact I have a numpad and I don’t use it much, I find the pie menu to be a faster way to work. But to answer your question, there was someone who was having trouble the other day, here:
https://cgcookie.mavenseed.com/community/18448-numpad-frustrations