The 68-year-old Radhakrishnan was a retired tutor from dental college and lived alone in the two-story house after separation from his wife some two years back.
His daughter who is a medical student and married to a doctor lives with her mother in Kottayam.
The police officials forcefully opened the door and found the decomposed body of the old man lying on the sofa.
The neighbours said that the old man used to spend his life privately while hardly speaking to anyone.
The body was handed over to relatives after postmortem and police have registered a case of unnatural death.