#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma optimize("unroll-loops")
#define fast ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define all(x) x.begin(), x.end()
#define rll(x) x.rbegin(), x.rend()
#define COMP(x) x.erase(unique(all(x)), x.end())
#define MOD 1000000007
#define MOD2 998244353
#define sz(x) (ll)x.size()
typedef __int128_t lll;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll,ll> pll;
typedef pair<ll, pll> PP;
const ll Lnf = 2e9;
ll n, k;
string s;
struct UF{
vector<ll> p;
UF(): p(1010101,-1){}
ll find(ll x){ if(p[x]<0)return x; return p[x] = find(p[x]); }
void merge(ll x, ll y){
x=find(x),y=find(y);
if(x==y)return; p[x]+=p[y]; p[y]=x;
}
} uf;
vector<ll> adj[1010101], ADJ[1010101];
vector<ll> getfail(string &s){
ll n = sz(s);
vector<ll> fail(n);
for(int i = 1, j = 0 ; i < n ; i++){
while(j>0 and s[i]^s[j]){
adj[i].push_back(j); adj[j].push_back(i);
j=fail[j-1];
}
if(s[i]==s[j])uf.merge(j,i), fail[i] = ++j;
else adj[i].push_back(j), adj[j].push_back(i);
}
return fail;
}
ll ans = 1;
bool vis[1010101];
char res[1010101];
ll dp[1010101];
void dfs(ll x){
ll c = sz(ADJ[x]);
ans = ans*(26-c)%MOD;
dp[x]=26-c;
}
void go(ll x){
ll b = 0;
for(auto next : ADJ[x]){
b |= (1<<(res[next]-'a'));
}
for(int i = 0 ; i < 26 ; i++)if(~b&(1<<i)){
res[x] = char(i+'a');
if(k>dp[x])k -= dp[x];
else break;
}
// cout<<x<<" "<<dp[x]<<" "<<k<<" "<<res[x]<<endl;
}
int main(){
fast;
cin>>s>>k; n = sz(s);
getfail(s);
for(int i = 0 ; i < n ; i++){
for(auto j : adj[i])if(uf.find(i) > uf.find(j))ADJ[uf.find(i)].push_back(uf.find(j));
}
for(int i = 0 ; i < n ; i++)sort(all(ADJ[i])), COMP(ADJ[i]);
for(int i = 0 ; i < n ; i++)if(i==uf.find(i))dfs(i);
ll prv = 1;
for(int i = n-1 ; i >= 0 ; i--)if(i==uf.find(i)){
ll p = prv;
if((lll)prv*dp[i] > LLONG_MAX)prv = LLONG_MAX;
else prv*=dp[i];
dp[i] = p;
}
cout<<ans<<"\n";
if((lll)dp[0]*26 < k)return !(cout<<"OVER");
for(int i = 0 ; i < n ; i++)if(i==uf.find(i))go(i);
for(int i = 0 ; i < n ; i++)cout<<res[uf.find(i)];
}
