Step 1: Divide the number into separate digits:
08795 => 0 8 7 9 5
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
0 to 8 = 8
8 to 7 = 1
7 to 9 = 2
9 to 5 = 4
5 to 0 = 5
Step 3: Combine the filters to a string:
8 1 2 4 5 = 81245