//In the name of God
#include <bits/stdc++.h>
#pragma GCC optimize("O2")
using namespace std;
typedef int ll;
typedef pair<ll, ll> pll;
const ll maxn = 3e5 + 100;
const ll lg = 19;
const ll mod = 1e9 + 7;
const ll inf = 1e9;
#define fast_io ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file_io freopen("input.txt", "r+", stdin);freopen("output.txt", "w+", stdout);
#define pb push_back
#define Mp make_pair
#define F first
#define S second
#define Sz(x) ll((x).size())
#define all(x) (x).begin(), (x).end()
#define lc (id << 1)
#define rc (lc | 1)
ll n, p[maxn], rnk[maxn], lcp[maxn], f[maxn];
string s;
vector<ll> vec[maxn];
ll mn[lg][maxn];
void bld(){
for(ll i = 0; i < n + 1; i++){
mn[0][i] = lcp[i];
}
for(ll i = 1; i < lg; i++){
for(ll j = 0; j + (1 << i) <= n + 1; j++){
mn[i][j] = min(mn[i - 1][j], mn[i - 1][j + (1 << (i - 1))]);
}
}
}
ll get(ll l, ll r){
if(l == r) return inf;
ll t = r - l;
ll i = f[t];
return min(mn[i][l], mn[i][r - (1 << i)]);
}
int main(){
fast_io;
for(ll i = 2; i < maxn; i++){
f[i] = f[i / 2] + 1;
}
cin >> s;
n = Sz(s);
s += '#';
vector<int> sa, rev;
sa.resize(n+1);
iota(sa.begin(),sa.end(),0);
sort(sa.begin(),sa.end(),
[&](int a,int b){
if(s[a]==s[b]) return a>b;
return s[a]<s[b];
});
vector<int> c(n+1,0),r(n+1),cnt(n+1);
for(int i=0;i<=n;i++) r[i]=s[i];
for(int len=1;len<=n;len*=2){
for(int i=0;i<=n;i++){
c[sa[i]]=i;
if(i>0 &&
r[sa[i-1]]==r[sa[i]] &&
sa[i-1]+len<=n &&
r[sa[i-1]+len/2]==r[sa[i]+len/2]) c[sa[i]]=c[sa[i-1]];
}
iota(cnt.begin(),cnt.end(),0);
copy(sa.begin(),sa.end(),r.begin());
for(int i=0;i<=n;i++){
int s1=r[i]-len;
if(s1>=0) sa[cnt[c[s1]]++]=s1;
}
c.swap(r);
}
rev.resize(n+1);
for(int i=0;i<=n;i++) rev[sa[i]]=i;
for(ll i = 0; i < n + 1; i++){
p[i] = sa[i];
rnk[i] = rev[i];
}
for(ll i = 0, k = 0; i < n + 1; i++){
if(rnk[i] == n){
k = 0;
continue;
}
ll j = p[rnk[i] + 1];
while(i + k < n + 1 && j + k < n + 1 && s[i + k] == s[j + k]) k++;
lcp[rnk[i]] = k;
if(k) k--;
}
bld();
vector<int> d1(n);
for (int i = 0, l = 0, r = -1; i < n; i++) {
int k = (i > r) ? 1 : min(d1[l + r - i], r - i + 1);
while (0 <= i - k && i + k < n && s[i - k] == s[i + k]) {
k++;
}
d1[i] = k--;
if (i + k > r) {
l = i - k;
r = i + k;
}
}
vector<int> d2(n);
for (int i = 0, l = 0, r = -1; i < n; i++) {
int k = (i > r) ? 0 : min(d2[l + r - i + 1], r - i + 1);
while (0 <= i - k - 1 && i + k < n && s[i - k - 1] == s[i + k]) {
k++;
}
d2[i] = k--;
if (i + k > r) {
l = i - k - 1;
r = i + k;
}
}
set<ll> st;
long long ans = 0;
for(ll i = n; i--;){
for(ll j : vec[i]){
st.erase(j);
}
vec[i].clear();
st.insert(i);
vec[i - d1[i]].pb(i);
auto it = st.rbegin();
while(it != st.rend()){
ll t = (*it - i) * 2 + 1;
if(t <= lcp[rnk[i] - 1]) break;;
ll l = rnk[i], r = n + 1;
while(r - l > 1){
ll mid = (l + r) >> 1;
if(get(rnk[i], mid) >= t) l = mid;
else r = mid;
}
ans = max(ans, ((long long)t) * (r - rnk[i]));
it++;
}
}
st.clear();
for(ll i = n - 1; i--;){
for(ll j : vec[i]){
st.erase(j);
}
if(d2[i + 1]) st.insert(i);
if(d2[i + 1]) vec[i - d2[i + 1]].pb(i);
if(st.empty()) continue;
auto it = st.rbegin();
while(it != st.rend()){
ll t = (*it - i) * 2 + 2;
if(t <= lcp[rnk[i] - 1]) break;
ll l = rnk[i], r = n + 1;
while(r - l > 1){
ll mid = (l + r) >> 1;
if(get(rnk[i], mid) >= t) l = mid;
else r = mid;
}
ans = max(ans, ((long long)t) * (r - rnk[i]));
it++;
}
}
cout << ans;
return 0;
}
