num = input()
digits = list(map(int, list(num)))
ans = 1

if all(d%4 == 0 for d in digits):
  ans *= 4
elif all(d%2 == 0 for d in digits):
  ans *= 2

if sum(digits)%9 == 0:
  ans *= 9
elif sum(digits)%3 == 0:
  ans *= 3
  
if all(d%5 == 0 for d in digits):
  ans *= 5

if len(set(digits)) == 1:
  print(num)
else:
  print(ans)