import math

n = int(input())
ans = n
for j in range(2, 64):
	l, r = 1, math.floor(n ** (1 / j)) + 100
	while l + 1 < r:
		mid = (l + r) // 2
		if pow(mid, j) <= n:
			l = mid
		else:
			r = mid
	ans = min(ans, n - pow(l, j) + j + l)

print(ans)