Step 1: Divide the number into separate digits:
16116 => 1 6 1 1 6
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
1 to 6 = 5
6 to 1 = 5
1 to 1 = 0
1 to 6 = 5
6 to 1 = 5
Step 3: Combine the filters to a string:
5 5 0 5 5 = 55055