#include <bits/stdc++.h>

#define LL long long

LL sum(LL x);

int main(void) {
  LL n; scanf("%lld", &n);

  for (LL i = n; i >= 1; i--) {
    if ((sum(n) * (n / i) + sum(n % i)) % i == 0) {
      printf("%lld\n", i);
      break;
    }
  }

  return 0;
}

LL sum(LL x) {
  return (1 + x) * x / 2;
}