To represent a number in scientific notation we need to move the decimal point and add powers of 10 in their place.
In this case we can move the decimal point (which is at the end of the number) until the place between the 6 and the 7:
And thus, since we moved the decimal point to the left 6 times, we add x10^6 in their place as follows:
In summary, we represent the exponent of the 10 as the number of times we moved the decimal point to the left.
Answer: 6.73x10^6