Step 1: Divide the number into separate digits:
34390 => 3 4 3 9 0
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
3 to 4 = 1
4 to 3 = 1
3 to 9 = 6
9 to 0 = 9
0 to 3 = 3
Step 3: Combine the filters to a string:
1 1 6 9 3 = 11693