Why is 11 (eleven) not pronounced onety-one or elebenty-leben, and why is it considered the ghetto way of saying eleven?
c.1200, elleovene, from Old English endleofan, literally "one left" (over ten), from Proto-Germanic *ainlif- (cf. Old Saxon elleban, Old Frisian andlova, Dutch elf, Old High German einlif, German elf, Old Norse ellifu, Gothic ainlif), a compound of *ain "one" (see one) + PIE *leikw- "leave, remain" (cf. Greek leipein "to leave behind;" see relinquish)
The name for the number has roots in other languages, whose words have actual meaning behind them.