Number of pixels is only one factor, and not the most important (except for marketing, where the desire for a simple message has led to "more Mpix = better" being repeated until many people assume it must be true).
Personally I'd say that the size of the sensor (area, not number of pixels), technology and quality of sensor (hard to judge unless you know the part number), quality of lens and quality of image processing software are all more important than the pixel count itself.
Early has suggested things you can do with the image processing. Funky has suggested the one thing you can do about the lens. As for the rest, the one thing that might be worth trying is experimenting with the ISO (effectively the film speed, more accurately the amplifier gain). High ISO allows shorter shutter speeds (less motion blur) but also higher noise. In good light you shouldn't need to worry, but in low light there is a trade-off. So if your camera app let's you control this (not all do) you could see whether forcing it to use a lower ISO helps with the noise.
Turning down sharpening might also help, as sharpening tends to exaggerate any noise that is present. I don't know whether your stock camera app will let you control either, but if not see what the other apps do.