prime_list = [True] * 2000000

def is_prime(sieve, x):
   for p in xrange(x+x, len(sieve), x):
       sieve[p] = False

for x in xrange(2, int(len(prime_list) ** 0.5) + 1):
    if prime_list[x]:
        is_prime(prime_list, x)

print sum(i for i in xrange(2, len(prime_list)) if prime_list[i])