Step 1: Divide the number into separate digits:
67662 => 6 7 6 6 2
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 6 = 0
6 to 2 = 4
2 to 6 = 4
Step 3: Combine the filters to a string:
1 1 0 4 4 = 11044