import sys
input = lambda : sys.stdin.readline().rstrip()
sys.setrecursionlimit(max(1000, 10**9))
write = lambda x: sys.stdout.write(x+"\n")

n = int(input())
ans = float("inf")
for x in range(1,n+1):
    if (n-x)%x==0:
        p = (n-x)//x
        if x<p:
            ans = min(ans, p)
    if x>=p:
        break
for p in range(2, n+1):
    if p*p>n:
        break
    v = 1
    val = 0
    for i in range(100):
        val += v
        v *= p
        if val>n:
            break
        if n%val==0 and n//val<p:
            ans = min(ans, p)
print(ans)