public class BitSetPrime {

	public static void main(String[] args) {
	BitSet p=new BitSet(2000000);
	p.flip(2,2000000); //Considering all numbers to be prime except 0 and 1
	for(int i=2 ;i<2000000;i++)
	{
		if(!p.get(i))
			continue;
		else 
		      // Set all multiples as not prime 
		      for(int j = 2*i; j < 2000000; j += i) 
		         p.set(j,false);
	}
	long sum=0;
	 for(int i = 2; i < 2000000; ++i) 
		    if( p.get(i) )  // Add all nos with bit set 
		      sum += i; 
	System.out.println(sum);
	
}
}