My phone keep installing an app even if I didn't do it

I was deleting some apps since my storage is almost full and saw in my apk installitations that i installed VIBER.. the icon is really similar to viber but its names "Base.apk" and other files related to it, so i delete it and it came back again.. asking permission to "install" but i didnt downloaded it.. i havent use viber yet.. i only use Facebook and messenger, i tried turning off downloading unknown sources but it keeps downloading itself, its really annoying.. i wonder if my phone is hacked or something?? is there anything i can do to stop it from downloading?