Question: how nallan chakravarthy name came?
Answer: CHAKRAVARTHY: Puranas hail, that Lord Tiruvengadamudaiyan gave the “Sudarsana-Panchajanya” to one Tondaiman Chakravarthy, for worship. ... The Lord gave him the Sudarsana-Panchajanya for worshipping him and hailed him “CHAKRAVARTHY.”