Step 1: Divide the number into separate digits:
65080 => 6 5 0 8 0
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
6 to 5 = 1
5 to 0 = 5
0 to 8 = 8
8 to 0 = 8
0 to 6 = 6
Step 3: Combine the filters to a string:
1 5 8 8 6 = 15886