Step 1: Divide the number into separate digits:
29075 => 2 9 0 7 5
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
2 to 9 = 7
9 to 0 = 9
0 to 7 = 7
7 to 5 = 2
5 to 2 = 3
Step 3: Combine the filters to a string:
7 9 7 2 3 = 79723