Step 1: Divide the number into separate digits:
2083 => 2 0 8 3
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
2 to 0 = 2
0 to 8 = 8
8 to 3 = 5
3 to 2 = 1
Step 3: Combine the filters to a string:
2 8 5 1 = 2851