import random
from fractions import gcd

N = raw_input()
if all(d==N[0] for d in N):
    print N
    exit()

ans = gcd(int(N), int(N[::-1]))
N = list(N)

for i in xrange(10**3):
    random.shuffle(N)
    ans = gcd(ans, int(''.join(map(str,N))))
    if ans == 1:
        print 1
        exit()
print ans