n = int(input())

def isok(mid,p):
    if mid ** p > n:return False
    else :return True
ans = n
for i in range(1,62):
    l = 0
    r = n+1
    while r-l > 1:
        mid =(r + l)//2
        if isok(mid,i):
            l = mid
        else:
            r = mid
    ans = min(n-l ** i + l + i,ans)
print(ans)