One of the lead dancers behind Karthik in 'Raja Rajathi Raja' song is Prabhudeva. His father Sundaram is the choreographer for the film.
Initially was being filmed with Nayagan. As Mani Ratnam couldn't manage both together, Agni Natchathiram was stopped until after Nayagan's release. (Source: Conversations with Mani Ratnam)
The soundtrack of this movie was an astronomical success and considered as one of the best works of legendary music director, Ilaiyaraaja till date.