Step 1: Divide the number into separate digits:
61255 => 6 1 2 5 5
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
6 to 1 = 5
1 to 2 = 1
2 to 5 = 3
5 to 5 = 0
5 to 6 = 1
Step 3: Combine the filters to a string:
5 1 3 0 1 = 51301