If you are eating a kebab and chip sandwich slathered in butter and a garlic sauce, then the number of calories it contains cannot be of that much interest to you.
I reckon a large donor alone would be knocking on the door of 2000KCal, without the chips - the chips would be adding perhaps as many as 1000KCal more.
The average maintenance calorie level for your average adult bloke - this would be just to keep the weight as it is, is around 2000 KCal a day. So that one meal rips the calorie guide down of the wall and then stamps all over it with hobnail boots....