N = gets.to_i

def prime?(n)
	i = 2
	while i * i <= n do
		return false if n % i == 0
		i += 1
	end
	return n != 1
end

prime = []

n = 10**5 + 1

while prime.length < 9 do
	prime << n if prime?(n)
	n += 1
end

beautiful = [1]

0.upto(8) {|i|
	i.upto(8) {|j|
		beautiful << prime[i] * prime[j]
	}
}

beautiful.sort!

puts beautiful[N-1]