题解 | #牛牛的二三七整除#

a=int(input())
if a%2==0 and a%3!=0 and a%7!=0:
    print("2")
elif a%2!=0 and a%3==0 and a%7!=0:
    print("3")
elif a%2!=0 and a%3!=0 and a%7==0:
    print("7")
elif a%2==0 and a%3==0 and a%7!=0:
     print("{} {}".format(2,3))
elif a%2==0 and a%3!=0 and a%7==0:
     print("{} {}".format(2,7))
elif a%2!=0 and a%3==0 and a%7==0:
     print("{} {}".format(3,7))
elif a%2==0 and a%3==0 and a%7==0:
    print("{} {} {}".format(2,3,7))
else:
    print("n")