Step 1: Divide the number into separate digits:
52806 => 5 2 8 0 6
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
5 to 2 = 3
2 to 8 = 6
8 to 0 = 8
0 to 6 = 6
6 to 5 = 1
Step 3: Combine the filters to a string:
3 6 8 6 1 = 36861