import sys
input=sys.stdin.readline
def I(): return int(input())
def MI(): return map(int, input().split())
def LI(): return list(map(int, input().split()))

def main():
    mod=10**9+7
    N=I()
    #約数列挙
    def make_divisors(n):
        divisors = []
        for i in range(1, int(n**0.5)+1):
            if n % i == 0:
                divisors.append(i)
                if i != n // i:
                    divisors.append(n//i)

        divisors.sort()
        return divisors
    
    d=make_divisors(N)
    flag=0
    for i in range(len(d)):
        a=d[i]
        b=d[-1-i]
        if b<=a:
            break
        if (b-a)%2==0:
            flag=1
            break
        
    if flag:
        print(1)
    else:
        print(-1)

        
    


main()