import sys
from operator import itemgetter
stdin=sys.stdin
sys.setrecursionlimit(10 ** 8)

ip=lambda: int(sp())
fp=lambda: float(sp())
lp=lambda:list(map(int,stdin.readline().split()))
sp=lambda:stdin.readline().rstrip()
Yp=lambda:print('Yes')
Np=lambda:print('No')
inf = 1 << 60
eps = 1e-9
sortkey = itemgetter(0)

n = ip()
ans = inf
for i in range(60):
    if i == 0:
        ans = min(ans, n)
    else:
        ok = 1
        ng = inf
        while abs(ok - ng) > 1:
            mid = (ok + ng) // 2
            temp = 1
            now = 0
            while now < i:
                temp *= mid
                if temp > n:
                    break
                now += 1
                
            if now == i:
                ok = mid
            else:
                ng = mid

        res = n - ok ** i + ok + i
        ans = min(ans, res)

print(ans)