import sys
input = sys.stdin.readline
from collections import *

def make_divs(n):
    divs = []
    
    for i in range(1, int(n**0.5)+1):
        if n%i==0:
            divs.append(i)
            
            if i!=n//i:
                divs.append(n//i)
    
    return divs
    
def judge(x):
    res = 0
    
    for i in range(k):
        res += pow(x, i)
        
        if res>N//d:
            return False
        
    return True
    
def binary_search():
    l, r = 2, 10**18
    
    while l<=r:
        m = (l+r)//2
        
        if judge(m):
            l = m+1
        else:
            r = m-1
    
    return r

N = int(input())

if N<=2:
    print(2)
    exit()
    
divs = make_divs(N)
ans = N-1

for d in divs:
    for k in range(1, 40):
        p = binary_search()
        
        if p>d and (pow(p, k)-1)//(p-1)==N//d:
            ans = min(ans, p)

print(ans)