Hindu counting system was purely decimal and distinct symbols for the numbers 1 - 9 existed already. A notation for high powers of ten existed already. Hindus used counting boards - had tens units columns. A lot of astronomical activity at this time - had to use large numbers. They knew about Babylonian place value system - knew about greek astronomy and its notation and may have encountered the small circle indicating a zero.
Nagari numerals are very similar to our own.
In books about AD570 they were writing 241960, - digits arranged in normal way zero is used, place value notation is used for the numerator and denominator of the fraction. This system quickly came into use - probably earliest symbol for zero was a dot and not a small circle. On its way to the West the Hindu method of writing numerals soon became known to the Arabs who had established a world empire from the 7th Century. Many mathematical books from the Greeks and Hindus were translated in Baghdad and travelled the West. The Arabs played an essential part in the dissemination of the numeral system - no number system of their own.