Not really possible to say with a huge degree of accuracy.
Some of the prize money is straightforward as it depends on how far we get and how many wins & draws we had in the group stage. Those incentive payments are fixed meaning that Barcelona and BATE Borisov get exactly the same for a win, a draw or for getting into the last 8 (for which alone we each get €6m).
But the rest depends on the Market Pool, which is a fixed pot of money that is split between all the clubs that played in the group stage and beyond. The split is first done on the basis of how much each national broadcast deal is worth as a proportion of the overall TV revenue. So if UEFA earn £1bn from the TV companies and the English TV rights make up 20% of that, the 4 English clubs get 20% of the Market Pool. Unless you know what that proportion is, it's difficult to say.
Once that split is done, the pots are divided into 2. The first part is distributed on the basis of where each club finished in their domestic league the previous season. The winners get 40%, second 30%, third 20% and forth get 10%. The other part is based on how many games each team played from the group stage onwards. As it stands, rags played 6, Arsenal & Chelsea both played 8 and we've played 10 so far (and that would be 12 if we get to the semi-final). If we do lose next week that means that English clubs will have played 32 games in total and we'd have played 10 of those, meaning we get 10/32nds of that half of the pot. If we go through, that will be at least 10/34ths.