Is there any such a dhikr?

Question

ASALAMUALAKUM. I have a question...i heard that there is this dhikr or dua that if you say it then Allah will wipe out your major sins called " Astagfirulah al adheem al lazi la ilaha ila huwal haiyul qayum wa a tubu illaih" does this clean you from the major sins? If not then is there any that can clean you from the major sins? How many times should i say it? Jazak Allah