Divisor 17047

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

The "Jonathan MacIntyre Test" for Divisibility by 17047

To determine if any number is divisible by 17047, apply the "Jonathan MacIntyre Test":

  1. If your number ("X") has 6 digits or more, separate the last (smallest) 5 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 6 digits, L = 0 and therefore R = X.
  2. Multiply L by 2282 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 5114 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 17047. That is, your original number is divisible by 17047 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 17047-times tables, it should be easy to visually see if Y is divisible by 17047. If the Y is still much larger than 17047, the above process can be repeated until it does reduce to within small multiples of 17047.

Easy!