import math

N = int(input())
ans = N
root = int(math.sqrt(N))
for i in range(1, root + 1):
    if N % i == 0:
        b = N // i
        if i % 2 == 1 and i >= 3:
            ans = min(ans, i)
        if b % 2 == 1 and b >= 3:
            ans = min(ans, b)

print(ans)