def sieve(n):
    is_prime = [True for _ in range(n+1)]
    is_prime[0] = False

    for i in range(2, n+1):
        if is_prime[i-1]:
            j = 2 * i
            while j <= n:
                is_prime[j-1] = False
                j += i
    table = [ i for i in range(1, n+1) if is_prime[i-1]]
    return [False]+is_prime, table


N = int(input())
ANS = [1]
P,T = sieve(10**5+2000)
for i in range(10**5+1,len(P)):
    if P[i]==False:
        ANS.append(i)
print(ANS[N-1])