N = int(input())
ans = N
if N == 1:
    print(1)
    exit()


def solve(N, k):
    l = 2
    r = N
    while r-l > 1:
        m = (l+r)//2
        if pow(m, k) <= N:
            l = m
        else:
            r = m
    return l+k+(N-pow(l, k))


for i in range(2, N.bit_length()):
    ans = min(ans, solve(N, i))

print(ans)