With 1 461 828 bearers, Mustafa is the 3rd most common masculine name in Turkey (2014 Data). With 422 008 bearers, Mustafa is the 7th most common masculine name in Sudan (2014 Data). With 7 435 bearers, Mustafa is the 2nd most common masculine name in Northern Cyprus.Source: https://forebears.io/forenames/mustafa
My surname is Mustafa, and although I don't hear of it much except within my family, in Cyprus and Turkey it is apparently as prevalent as Smith is in England. It means 'The Chosen One' and many people gave their children the surname as a way to honour Mustafa Ataturk Kemal who is considered the founder of contemporary Turkey. This explains its popularity in modern day Turkey. My grandfather's parents gave him the surname Mustafa even though their own was Hussein, as he was born around the time of Ataturk's prevalence.
https://en.m.wikipedia.org/wiki/Mustafa_Dzhemilev