A nano is essentially one-billionth
or 1/1,000,000,000.
Since writing all these zeroes is inefficient and can easily lead into errors, we'll just use scientific notation instead.
A nanoliter is
liters.
So we have
liters.
A liter is 4.22675 cups. So now we can multiply 4.22675 by 6.25 * 10^13.
Use a calculator...
you get 26.4171875 * 10^13.
*Note: There may be slight precision errors. This is inevitable when you're working with very large numbers, as the smallest initial change can spiral into much larger differences.