It is a very common expression used by arrogant people who believe they are more than the rest and who believe they have some "crown" to treat the rest badly, in the end who they are addressing surely is not interested in the power or money that person has and normally the most appropriate response they give is "it is true, I don't know who you are, but I do know who I am. . "Some synonyms, words or similar expressions may be I am the maximum, no one like me,
