n = int(input())

def check(n):
    divisors = []
    for i in range(1, int(n**0.5)+1):
        if n % i == 0:
            j = n//i
            if 2 <= i <= 10**5 or 2 <= j <= 10**5:
                return False
    else:
        return True

ans = []
i = 1
while len(ans) < n:
    if check(i):
        ans.append(i)
    i += 1
print(ans[n-1])