If you have enough apps on the phone, that can take an hour or more. If it's been doing it longer, you probably have to reflash the firmware. How you do that, and whether you can do it without losing all your data, depends on the phone you have. ("Android" is just a program running in Linux, which is the operating system of the phone - that doesn't tell us which phone it is.)
If you want to go further, posting the phone and getting instructions, please join the Android Central community, so you can keep the conversation here and not start a new one.
Welcome to Android Central! I've been seeing a number of threads mentioning that this could be due to the Zedge app. Uninstall it, if you have it on your phone.