def fun(N): result = [1] i = 1 count = 1 while count < N: i += 1 j = i while j%2 == 0: if j!=1: j = j / 2 if j == 1: result.append(i) count += 1 break while j%2!=0 and j%3==0: if j!=1: j = j / 3 if j == 1: result.append(i) count += 1 break while j%2!=0 and j%3!=0 and j%5==0: if j!=1: j = j / 5 if j == 1: result.append(i) count += 1 break return result[N-1] inp = input() inp = int(inp) print(fun(inp))