Step 1: Divide the number into separate digits:
92012 => 9 2 0 1 2
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
9 to 2 = 7
2 to 0 = 2
0 to 1 = 1
1 to 2 = 1
2 to 9 = 7
Step 3: Combine the filters to a string:
7 2 1 1 7 = 72117