Step 1: Divide the number into separate digits:
97130 => 9 7 1 3 0
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
9 to 7 = 2
7 to 1 = 6
1 to 3 = 2
3 to 0 = 3
0 to 9 = 9
Step 3: Combine the filters to a string:
2 6 2 3 9 = 26239