Rajan moved to Mangalore in 1959. He discovered his exceptional ability to memorize numbers at the very young age of 5 during a party hosted by his family. During the party, Rajan wandered to a parking lot and committed the license plate numbers of every guest's car for recitation later.
In 1977, after losing interest in engineering, Rajan set to memorize substantial parts of pi. On July 5, 1981, he recited from memory the first 31,811 digits of pi. This secured him a place in the 1984 Guinness Book of World Records, and he has been featured on Larry King Live and Reader's Digest.
Rajan received his bachelor's degree in psychology in 1984 and his master's degree in clinical psychology from the University of Mysore in 1986 during his extended participation in memory study. Though as research on Rajan progressed, his digit span was found to be nearly ten times the average, it is estimated that, before the effects of practice, it was at a more modest but nonetheless exceptional 15 digits.
Although Rajan is adept at remembering numbers, he nevertheless displays only an average memory when it comes to prose passages or geometric shapes.
Rajan holds the position of Distinguished Lecturer at the University of Tennessee, where he teaches courses in learning and thinking as well as cognitive psychology.
- Rajan Mahadevan recites 31,811 digits of ã from memory July 5 in History
- DAVID R. SHANKS, Science Spectra, 1999, Number 18. Outstanding Performers: Created, Not Born? NEW RESULTS ON NATURE VS. NURTURE.
- "Unexceptional spatial memory in an exceptional memorist", Biederman et al., Journal of Experimental Psychology Learn Mem Cogn, 1992 May;18(3):654-7. 
- "The Man With the Endless Memory;Rajan Mahadevan Is Trying to Memorize 100,000 Digits. For Him, It's Easy as Pi", Washington Post article June 18, 1989. 
- "Memory Search by a Memorist", Thompson et al. Lawrence Erlbaum Associates, Inc.,New Jersey, 1993