Step 1: Divide the number into separate digits:
64713 => 6 4 7 1 3
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
6 to 4 = 2
4 to 7 = 3
7 to 1 = 6
1 to 3 = 2
3 to 6 = 3
Step 3: Combine the filters to a string:
2 3 6 2 3 = 23623