import sys
import math

n = int(input())
ans = n
for i in range(2, 61):
    l = 1
    r = n
    while r - l > 1:
        m = (l + r) // 2
        if (m**i) > n:
            r = m
        else:
            l = m
    ans = min(ans, l + i + n - (l**i))
print(ans)