Step 1: Divide the number into separate digits:
49011 => 4 9 0 1 1
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
4 to 9 = 5
9 to 0 = 9
0 to 1 = 1
1 to 1 = 0
1 to 4 = 3
Step 3: Combine the filters to a string:
5 9 1 0 3 = 59103