wrong answer in prime pallindrome .please tell problem?

When I ran this code int turbo c++ the answer to 31 was coming correctly to be 101.But when I submitted it was giving that "wrong answer"!Please tell me problem?
#include<stdio.h>
long int pal(long int l)
{ long int rev=0,rem;
long int x=l;
while(x!=0)
{
rem=x%10;
x=x/10;
rev=(rev*10)+rem;
}
if(rev==l)
return(1);
else
return(0);
}

long int prime(long int b)
{ long int c=0;
for(long int i=1;i<=b;i++)
{ if(b%i==0)
c++;
}
if(c==2)
return(1);
else
return(0);
}

main()
{
long int n,m,k=0;
scanf("%d",&n);
for(long int i=n+1;i<=1000000;i++)
{
if(pal(i))
{
if(prime(i))
k=1;
}
if(k==1)
{m=i; break;}

}
printf("%d",m);
}

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