def check(x,D):
    res=0
    while(x):
        res+=x
        x//=2
        if res==D:
            return True
    return False

D=int(input())
ans=D
for x in range(max(0,D//2-200),D//2+200):
    if check(x,D):
        ans=min(ans,x)
print(ans)