Step 1: Divide the number into separate digits:
4058 => 4 0 5 8
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
4 to 0 = 4
0 to 5 = 5
5 to 8 = 3
8 to 4 = 4
Step 3: Combine the filters to a string:
4 5 3 4 = 4534