4*6*6*6*3 numbers. Any of digits 4, 5, 7, 8 in the 1-st (leftmost) position: 4 choices. Any of digits 1, 2, 4, 5, 7, 8 in the 2-nd position: 6 choices. Any of digits 1, 2, 4, 5, 7, 8 in the 3-rd position: 6 choices. Any of digits 1, 2, 4, 5, 7, 8 in the 4-th position: 6 choices. Any of digits 2, 4, 8 in the 5-th position: 3 choices.