TRC

How many digits can you multiply in your head? For most normal people single digit multiplication is generally possible while two-digit multiplication can quickly become out of reach. Mathematical prodigies are capable of multiplying very large numbers. But multiplying is not the only thing that some of them can do. They can go backwards and derive the factors and roots of numbers to a very high level of precision. One such prodigy is a funny 70 year old woman from India called Shakuntala Devi. She is the only prodigy that I have actually seen live. It’s not an experience that can be forgotten easily.


She visited my school to give a demonstration and I remember us (including the math teachers) not being able to come up with a single calculation question that could stump her. Beyond number calculation she was also very adept at days and dates and was able to come up with the days of the week for pretty much any day in history regardless of whether it was before or after the invention of the Gregorian calendar.
She has been entered into the Guinness Book of World Records for multiplying two 13-didgit numbers randomly selected by a computer. She took all of 28 seconds to come up with the answer and it is said that most of that time was taken to dictate the 26 digit answer digit by digit! The other phenomenal calculation she is known for is the mental extraction of the 23^rd root of a 201 digit number.
What is unusual about her is that she is a child prodigy whose talent never faded. She first started showing her abilities at a very young age, but unlike many other prodigies has been able to maintain it into adulthood and still does demonstrations for eager groups of students. Here is a video of one such demonstration she did in a school in Dubai. The audio is not particularly clear, but the scene feels quite familiar to me.