Divisor 5741

Prime Number:
Yes!
Divisibility test:
The "Xtr3m3 Test"
Test Discovered by:
Matt Parker
Date:
11/11/2024

The "Xtr3m3 Test" for Divisibility by 5741

To determine if any number is divisible by 5741, apply the "Xtr3m3 Test":

  1. If your number ("X") has 8 digits or more, separate the last (smallest) 7 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 8 digits, L = 0 and therefore R = X.
  2. Multiply L by 822 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 574 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 5741. That is, your original number is divisible by 5741 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 5741-times tables, it should be easy to visually see if Y is divisible by 5741. If the Y is still much larger than 5741, the above process can be repeated until it does reduce to within small multiples of 5741.

Easy!