The Aryabhata Number System

In Computer Science, there are computations using binary or hexadecimal system, but for most people, the common system is the decimal system. Indian mathematicians did not restrict themselves to one system for computation. During the time of Aryabhatta, there were at least three methods of writing numbers. The most popular way of writing was using the Samskritam number system. Mathematicians like Varahamihira and Bhaskaracharya used a different system called the bhooth sankhya. Aryabhatta, though, invented his own system which was a new contribution.

In the Aryabhatta number system, the Samskritam letters from क to म carry values from 1 to 25. Letters from य to ह carry values 30, 40, 50… 80. Whenever an इ-kaara is used, the value is multiplied by 100. When an उ-kaara is used, the multiplier is 10,000, ऋ-kaara multiplies it by 1,000,000. To illustrate with example

• च = 6
• चि = 600
• चु = 60,000
• च्र = 6,000,000
• कुचि = कु + चि = 10,000 + 600 = 10, 600

Reference: Aryabhateeya by Aryabhata (by Prof K S Sukla & Prof. K V Sarma. Commentary by Dr. N. Gopalakrishnan), Published by Indian Institute of Scientific Heritage, Thiruvananthapuram