#include <iostream>
#include <bits/stdc++.h>
using namespace std;
const int MAX=3*1e5;
int n;
string inp;
vector<int>sa;
long long outp;
int IS(int a,vector<int>&arr,vector<int>&s,vector<bool>&sl,vector<int>&lms){
int i;
vector<int>num(a),num2(a+1);
for(i=0;i<s.size();i++){
num[s[i]]++;
num2[s[i]+1]++;
}
for(i=1;i<a;i++){
num[i]+=num[i-1];
num2[i]+=num2[i-1];
}
fill(arr.begin(),arr.end(),-1);
for(i=lms.size()-1;i>=0;i--)arr[--num[s[lms[i]]]]=lms[i];
for(i=0;i<s.size();i++)if(arr[i]>0&&!sl[arr[i]-1])arr[num2[s[arr[i]-1]]++]=arr[i]-1;
for(i=0;i<lms.size();i++)num[s[lms[i]]]++;
for(i=s.size()-1;i>=0;i--)if((arr[i]>0)&&sl[arr[i]-1])arr[--num[s[arr[i]-1]]]=arr[i]-1;
return 0;
}
vector<int>SAIS(int a,vector<int>&s){
int i;
vector<int>arr(s.size()),lms,lms2,s2;
vector<bool>sl(s.size());
sl[s.size()-1]=1;
for(i=s.size()-2;i>=0;i--){
sl[i]=(s[i]<s[i+1])||((s[i]==s[i+1])&&sl[i+1]);
if(!sl[i]&&sl[i+1])lms.push_back(i+1);
}
reverse(lms.begin(),lms.end());
IS(a,arr,s,sl,lms);
lms2.reserve(lms.size()),s2.reserve(lms.size());
for(i=0;i<s.size();i++)if(arr[i]>0&&sl[arr[i]]&&!sl[arr[i]-1])lms2.push_back(arr[i]);
int c=0;
arr[s.size()-1]=c;
for(i=1;i<lms2.size();i++){
int x=lms2[i-1];
int y=lms2[i];
if(s[x]<s[y])c++;
else{
while(true){
x++;
y++;
if(s[x]<s[y]){
c++;
break;
}
else if((sl[x]&&!sl[x-1])||(sl[y]&&!sl[y-1]))break;
}
}
arr[lms2[i]]=c;
}
if(c+1<lms2.size()){
for(i=0;i<lms.size();i++)s2.push_back(arr[lms[i]]);
vector<int>arr2=SAIS(c+1,s2);
for(i=0;i<lms.size();i++)lms2[i]=lms[arr2[i]];
}
IS(a,arr,s,sl,lms2);
return arr;
}
vector<int>suffixArray(string&s){
vector<int>s2(s.begin(),s.end());
s2.push_back(0);
s2=SAIS(256,s2);
s2.erase(s2.begin());
return s2;
}
vector<int>d1;
void oddManacher(){
d1=vector<int>(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&&inp[i-k]==inp[i+k])k++;
d1[i]=k--;
if(i+k>r){
l=i-k;
r=i+k;
}
}
}
vector<int>d2;
void evenManacher(){
d2=vector<int>(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&&inp[i-k-1]==inp[i+k])k++;
d2[i]=k--;
if(i+k>r){
l=i-k-1;
r=i+k;
}
}
}
int lzy[1<<20][2];
void delazy(int t,int a,int b,int c){
if(a==b||lzy[c][t]==-1)return;
lzy[2*c+1][t]=lzy[c][t];
lzy[2*c+2][t]=lzy[c][t];
lzy[c][t]=-1;
}
int querySeg(int t,int a,int b,int p,int c){
if(a>p||b<p)return -1;
delazy(t,a,b,c);
if(a==b)return lzy[c][t];
return max(querySeg(t,a,(a+b)/2,p,2*c+1),querySeg(t,(a+b)/2+1,b,p,2*c+2));
}
void updateSeg(int t,int a,int b,int be,int en,int c,int v){
if(a>en||b<be)return;
delazy(t,a,b,c);
if(a>=be&&b<=en){
lzy[c][t]=v;
return;
}
updateSeg(t,a,(a+b)/2,be,en,2*c+1,v);
updateSeg(t,(a+b)/2+1,b,be,en,2*c+2,v);
}
int bit[MAX+1];
int queryBit(int be,int en){
int ret=0;
for(en++;en>0;en-=en&-en)ret+=bit[en];
for(;be>0;be-=be&-be)ret-=bit[be];
return ret;
}
void updateBit(int p,int v){
for(p++;p<=n;p+=p&-p)bit[p]+=v;
}
set<int>cnt[MAX];
void deleteRange(int be,int en,int p){
while(cnt[p].lower_bound(be)!=cnt[p].end()){
int cur=*cnt[p].lower_bound(be);
if(cur>en)break;
updateBit(cur,-1);
cnt[p].erase(cnt[p].find(cur));
}
}
void solve(int pty,vector<int>&d){
memset(lzy,-1,sizeof(lzy));
memset(bit,0,sizeof(bit));
for(int i=0;i<n;i++)if(d[sa[i]]!=0)updateBit(i,1);
for(int i=0;i<n;i++)cnt[i].clear();
for(int i=0;i<n;i++)cnt[d[sa[i]]].insert(i);
for(int i=0;i<n;i++){
int cap=querySeg(0,0,n-1,i,0);
int l=i;
int r=querySeg(1,0,n-1,i,0);
if(r==-1)r=n-1;
int m=(l+r)/2;
for(int j=cap+1;j<d[sa[i]];j++){
while(r-l>1){
if(inp[sa[i]+j]==(sa[m]+j<n?inp[sa[m]+j]:'$'))l=m;
else r=m;
m=(l+r)/2;
}
if(inp[sa[i]+j]==(sa[r]+j<n?inp[sa[r]+j]:'$'))m=r;
else m=l;
outp=max(outp,(long long)(2*j-pty+2)*queryBit(i,m));
deleteRange(i,m,j+1);
updateSeg(0,0,n-1,i,m,0,j);
updateSeg(1,0,n-1,i,m,0,m);
r=m;
l=i;
}
}
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin>>inp;
n=inp.length();
sa=suffixArray(inp);
oddManacher();
evenManacher();
solve(1,d1);
solve(0,d2);
cout<<outp<<"\n";
}
