def mkp(n):
  P = [2]
  p = [2]
  x = 3
  while len(P) < n:
    for i in p:
      if x % i == 0:
        break
    else:
      P.append(x)
    while x > p[-1]**2:
      p.append(P[len(p)])
    x += 2
  return P

primes = mkp(1000)

def factor(x):
  out = []
  for p in primes:
    if p * p > x:
      break
    if x % p == 0:
      count = 0
      while x % p == 0:
        x /= p
        count += 1
      out.append(count)
  if x > 1:
    out.append(1)
  return out


def sum(x):
  pre = factor(x)
  out = 1
  for i in pre:
    out *= i * 2 + 1
  return (out + 1) / 2


def maxx(x):
  n = 4
  while sum(n) < x:
    n += 1
  return n


print maxx(100000)