require 'prime'
n = gets.to_i
if n == 1
	puts 1
else
	a =
		Prime.each(10**5 + 1000).select { |i| i > 10**5 }.repeated_combination(
			2
		).map { |v| v[0] * v[1] }.sort.uniq
	puts a[n - 2]
end