from itertools import *
from bisect import *
from collections import *
from heapq import *
import sys

sys.setrecursionlimit(10 ** 6)

def II(): return int(sys.stdin.readline())
def MI(): return map(int, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def SI(): return sys.stdin.readline()[:-1]
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
int1 = lambda x: int(x) - 1
def MI1(): return map(int1, sys.stdin.readline().split())
def LI1(): return list(map(int1, sys.stdin.readline().split()))
p2D = lambda x: print(*x, sep="\n")
dij = [(1, 0), (0, 1), (-1, 0), (0, -1)]

def gcd(a,b):
    while b:a,b=b,a%b
    return a

def main():
    s=SI()
    num=set()
    for c in s:
        c=int(c)
        num.add(c)
    if len(num)==1:
        print(s)
        exit()
    g=0
    for a in num:
        if a:
            if g:g=gcd(g,a)
            else:g=a
    g*=9
    g=gcd(g,int(s))
    print(g)

main()