You can
put this solution on YOUR website!
4503599627400000
Put a decimal between the first digit 4 and the 5 next to it:
4.503599627400000
Now count how many digits there are after the decimal.
I count 15. Remember that number, 15.
Drop off all the trailing zeros at the end:
4.5035996274
Remembering that number 15, put on ×1015
4.5035996274×1015 <-- final answer
Edwin