44. MORE DIVISIBILITY TESTS
 
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Pick-up the technique

5. Test for 17 ( '- 5 x units' )
Subtract 5 times units digit from rest of number;
Repeat if needed; Test by 17.

6. Test for 19 ( '+ 2 x units' )
Add 2 times units digit to rest of the number;
Repeat if needed; Test by 19.

7. Test for 23 ( '+ 7 x units' )

8. Test for 29 ( '+ 3 x units' )

9. Test for 31 ( '- 3 x units' )

10. Test for 37 ( '- 11 x units' )

11. Test for 41 ( '- 4 x units' )
NOTE:
432 = 1849.

So, with the above techniques, one can check numbers upto 1848 for primality.