Step 1: Divide the number into separate digits:
28669 => 2 8 6 6 9
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
2 to 8 = 6
8 to 6 = 2
6 to 6 = 0
6 to 9 = 3
9 to 2 = 7
Step 3: Combine the filters to a string:
6 2 0 3 7 = 62037