document.write( "Question 117716: hello sir,
\n" ); document.write( "This is Prakash Baskaran.
\n" ); document.write( "Is there any shortcut method to find out whether a number is prime or not?? for simple numbers it is easy, but what is I'am given a huge num,
\n" ); document.write( "another condition being that, the num is not divisible by any numbers from 1-15. \r
\n" ); document.write( "\n" ); document.write( "Pls do reply to my mail\r
\n" ); document.write( "\n" ); document.write( "Prakash Baskaran \n" ); document.write( "

Algebra.Com's Answer #85707 by MathLover1(20850) $\"\"$ $\"About$

You can put this solution on YOUR website!

\n" ); document.write( "“Fermat's little theorem” can help you to determine whether number is prime or not. One version of the theorem states:\r
\n" ); document.write( "\n" ); document.write( "If $\"+p\"$ is a $\"prime\"$ $\"+number\"$ and $\"b\"$ any whole number, then $\"b%5Ep+%96+b\"$ is a multiple of $\"+p\"$ . \r
\n" ); document.write( "\n" ); document.write( "Examples: \r
\n" ); document.write( "\n" ); document.write( " if $\"p+=+7\"$ and $\"b+=2\"$ , the theorem correctly predicts that $\"7\"$ divides evenly into $\"2%5E7+%96+2\"$ , or $\"126\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"4%5E3+-+4+=+60\"$ is divisible by $\"3\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"7%5E2+-+7+=+42\"$ is divisible by $\"2\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"%28-3%29%5E7+-+%28-3%29+=+-2184\"$ is divisible by $\"7\"$
\n" ); document.write( "
\n" ); document.write( " $\"2%5E97+-+2+=+158+456+325+028+528+675+187+087+900+670\"$ is divisible by $\"+97\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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