Step 1: Divide the number into separate digits:
27720 => 2 7 7 2 0
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
2 to 7 = 5
7 to 7 = 0
7 to 2 = 5
2 to 0 = 2
0 to 2 = 2
Step 3: Combine the filters to a string:
5 0 5 2 2 = 50522