#include using namespace std; typedef long long int ll; typedef pair P; typedef vector VI; typedef vector VVI; const ll MOD = 1000000007; const ll INF = 1e18; #define REP(i, n) for(int i = 0; i < n; i++) #define ALL(v) v.begin(), v.end() ll power(ll x, ll y) { if (y==0) return 1; else if (y==1) return x%MOD; else if (y%2==0) { ll pow=power(x,y/2); return (pow*pow)%MOD; } else { ll pow=power(x,y/2); return ((pow*pow)%MOD)*x%MOD; } } ll divid(ll x, ll y) { return ((x%MOD)*power(y,MOD-2))%MOD; } int main() { string s; cin >> s; int n=s.size(); ll ans=n*power(2,n-1)%MOD; VI p(26,0); REP(i,n){ p[s[i]-'a']+=power(2,n-1-i); p[s[i]-'a']%=MOD; } REP(i,n){ p[s[i]-'a']-=power(2,n-1-i); p[s[i]-'a']=(p[s[i]-'a']+MOD)%MOD; ans-=p[s[i]-'a']*power(2,i)%MOD; ans=(ans+MOD)%MOD; } cout << ans << endl; return 0; }