Step 1: Divide the number into separate digits:
67636 => 6 7 6 3 6
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
6 to 7 = 1
7 to 6 = 1
6 to 3 = 3
3 to 6 = 3
6 to 6 = 0
Step 3: Combine the filters to a string:
1 1 3 3 0 = 11330