Step 1: Divide the number into separate digits:
19122 => 1 9 1 2 2
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
1 to 9 = 8
9 to 1 = 8
1 to 2 = 1
2 to 2 = 0
2 to 1 = 1
Step 3: Combine the filters to a string:
8 8 1 0 1 = 88101