Step 1: Divide the number into separate digits:
0893 => 0 8 9 3
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
0 to 8 = 8
8 to 9 = 1
9 to 3 = 6
3 to 0 = 3
Step 3: Combine the filters to a string:
8 1 6 3 = 8163