Step 1: Divide the number into separate digits:
96213 => 9 6 2 1 3
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
9 to 6 = 3
6 to 2 = 4
2 to 1 = 1
1 to 3 = 2
3 to 9 = 6
Step 3: Combine the filters to a string:
3 4 1 2 6 = 34126