A 14-year-old human calculator

Meet Aaryan Shukla, a 14-year-old boy from India, and one of those kids who has this mysterious ability to do mathematics in his head–very rapidly. Here he tries to set a number of Guinness records in one day. He set six!

The records (he tried for ten): all involve the speed with wich Aaryan got a successful answer.

Adding  100 4-digit numbers
Adding 200 4-digit numbers
Adding 50 5-digit numbers
Dividing a 20-digit number by a 10-digit number
Multiplying two five digit numbers (a set of 10)
Mutiplying two eight-digit numbers (a set of 10)

Of course you could produce an infinite number of categories to test, but it’s clear this young man has amazing abilities. Does anyone know how he does it? I have no idea! And I wonder if this skill could help him get a job, or whether his abilities translate into other abilities that could secure lucrative employment.