Step 1: Divide the number into separate digits:
16148 => 1 6 1 4 8
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 4 = 3
4 to 8 = 4
8 to 1 = 7
Step 3: Combine the filters to a string:
5 5 3 4 7 = 55347