def divisor(n):
    d = []
    i = 1
    while i * i <= n:
        if n % i == 0:
                d.append(i)
            
        i += 1
    
    return d
        
n = int(input())
d = divisor(n)

ans = -1
for small in d:
    big = n // small
    
    if (big - small) % 2 == 0:
        if 0 < big - (big - small) // 2: 
            ans = 1
            break

print(ans)