Step 1: Divide the number into separate digits:
16478 => 1 6 4 7 8
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
1 to 6 = 5
6 to 4 = 2
4 to 7 = 3
7 to 8 = 1
8 to 1 = 7
Step 3: Combine the filters to a string:
5 2 3 1 7 = 52317