The color black is not really black. Why?

I love my Painter products. I can draw like I've always wanted to. I am, however, frustrated with a certain issue. Black is not black. It looks like someone ran it through a washing machine a few times. It is more of a dark charcoal and not a true black. If I draw in Painter, then bring it into another program, or just save the image, there is a noticeable difference between the black colors. I have frustrated myself to no end trying to research this problem. I try searching for answers on the web but the keywords are too vague to find the answer I am looking for. I get everything from black animals to black and white drawings. None point me in the direction of a solution. I did however find one solution, involving a different program that suggested changing CMYK pallets but Painter is an RGB (which are obviously set to all zeros).

Can someone please point me to a solution? This is making me absolutely bonkers.