#include <bits/stdc++.h>
using namespace std;

const int64_t MOD = 1e9+7;
void add(int64_t& a, int64_t b){
    a = (a+b) % MOD;
}
void mul(int64_t& a, int64_t b){
    a = a*b % MOD;
}

int64_t power_mod(int64_t num, int64_t power){
    int64_t prod = 1;
    num %= MOD;
    while(power > 0){
        if(power&1) prod = prod * num % MOD;
        num = num * num % MOD;
        power >>= 1;
    }
    return prod;
}

int64_t extgcd(int64_t a, int64_t b, int64_t& x, int64_t& y){
    int64_t d = a;
    if(b != 0){
        d = extgcd(b, a%b, y, x);
        y -= (a/b) * x;
    }else{
        x = 1; y = 0;
    }
    return d;
}

int64_t inv_mod(int64_t a){
    int64_t x, y;
    extgcd(a, MOD, x, y);
    return (MOD + x%MOD) % MOD;
}

int main(){
    string S;
    cin >> S;
    int N = S.size();

    int64_t ans = N * power_mod(2, N-1) % MOD;
    int64_t iv2 = inv_mod(2), pw2 = power_mod(2, N-2);
    vector<int64_t> sum(26);
    for(char c : S){
        int v = c-'a';
        add(ans, MOD - sum[v]);
        for(auto& s : sum) mul(s, iv2);
        add(sum[v], pw2);
    }
    cout << ans << endl;
    return 0;
}