Divisor 19583

Prime Number:
Yes!
Divisibility test:
The "Marty Otzenberger Test"
Test Discovered by:
Matt Parker
Date:
11/11/2024

The "Marty Otzenberger Test" for Divisibility by 19583

To determine if any number is divisible by 19583, apply the "Marty Otzenberger Test":

  1. If your number ("X") has 11 digits or more, separate the last (smallest) 10 digits from the rest. This makes two smaller numbers, call them Left and Right (note: don't add in trailing zeros to L). If there are fewer than 11 digits, L = 0 and therefore R = X.
  2. Multiply L by 201 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and add 5875 times the digit you just crossed off. Call this final result "Y".
  4. Y will be much smaller than X, but we have preserved divisibility by 19583. That is, your original number is divisible by 19583 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 19583-times tables, it should be easy to visually see if Y is divisible by 19583. If the Y is still much larger than 19583, the above process can be repeated until it does reduce to within small multiples of 19583.

Easy!