To solve this arithmetic expression, follow the order of operations: parentheses first, then multiplication and division from left to right, and finally addition and subtraction from left to right.

Start with the multiplication and division:
204 * 3200 = 652800
840560 / 280 = 3002

Substitute these values back into the expression:
201040 - 168942 + 652800 + 3002

Now, perform the addition and subtraction:
201040 - 168942 = 32098
32098 + 652800 + 3002 = 685900

Therefore, the solution to the expression 201040-168942+204 *3200+840560/280 is 685900.