private static void primeNumber(long limit){ long i, num; int cnt; for(i = 1; i = 1 ; num--){ if(i % num == 0){ cnt += 1; } } if(cnt == 2){ System.out.print(""+ i +" "); } } } pass '999999999' as an argument to above function it will print all the prime numbers in between (0 -999999999)