n=int(input())
if n==1:
    print(1)
    exit()
import math
def isprime(n):
    if n < 2:
        return False
    if n == 2:
        return True
    if n % 2 == 0:
        return False
    for i in range(3, int(math.sqrt(n)) + 1, 2):
        if n % i == 0: return False
    return True

prime=[]
for i in range(10**5+1,10**5+200):
    if isprime(i):
        prime.append(i)
        if len(prime)>=10:
            break
kouho=set()
for i in range(len(prime)):
    for j in range(i+1,len(prime)):
        kouho.add(i*j)
kouho=list(kouho).sort()
print(kouho[n-2])