Step 1: Divide the number into separate digits:
40337 => 4 0 3 3 7
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
4 to 0 = 4
0 to 3 = 3
3 to 3 = 0
3 to 7 = 4
7 to 4 = 3
Step 3: Combine the filters to a string:
4 3 0 4 3 = 43043