c = int(input())
now = 0
N = 1000
while 1:
    nxt = now + 1
    t = nxt * nxt * nxt * nxt * nxt + nxt * N * N * N * N - c * N * N * N * N * N
    if t <= 0:
        now = nxt
    else:
        break

if now >= 1000:
    t = now // 1000
    now %= 1000
else:
    t = 0
ans = str(now / 1000)
ans = ans + (5-len(ans)) * "0"
if t:
    print(str(t) + ans[1:])
else:
    print(ans)