Step 1: Divide the number into separate digits:
38066 => 3 8 0 6 6
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
3 to 8 = 5
8 to 0 = 8
0 to 6 = 6
6 to 6 = 0
6 to 3 = 3
Step 3: Combine the filters to a string:
5 8 6 0 3 = 58603