final_7.py

n = int(input()) max_dl = 0 if len(str(n)) == 4: for i in range(2, n + 1): if str(i) in str(n): k = False for dl in range(2, i // 2 + 1): if i % dl == 0: k = True break if k: continue else: max_dl = max(max_dl, i) print(max_dl)