Mental calculation) is a 1986 Indian Tamil-language film directed by R. C. Sakthi,[1] starring Vijayakanth, Sarath Babu, Rajesh, Ambika and Radha.

Kamal Haasan acted in a guest appearance.

[3] The film was produced by J. Maonohar, Radha's makeup man.

The film began production with song recording during the launch at Prasad Studios.

[6][7] Jayamanmadhan of Kalki wrote Manakanakku is a crowning achievement for director R. C. Sakthi who weaved a dense story neatly.