#include<iostream>
#include<string>
#include<iomanip>
#include<cmath>
#include<vector>
#include<algorithm>
#include<utility>

using namespace std;

#define int long long
#define endl "\n"

constexpr long long INF = (long long)1e18;
constexpr long long MOD = 1'000'000'007; 

struct fast_io {
	fast_io(){
		std::cin.tie(nullptr);
		std::ios::sync_with_stdio(false);
	};
} fio;

class binomial_coefficients {
	long long MAX_VAL;
	vector<long long> fac, mmi;

public:

	binomial_coefficients(){
	}
	
	binomial_coefficients(long long num){
		init(num);
	}
	
	~binomial_coefficients(){
		
	}
	
	void init(long long num){
		MAX_VAL = num+1; 
		fac.resize(MAX_VAL);
		mmi.resize(MAX_VAL);
		
		factorial_mod();
		modular_multiplicatibe_inverse();
	}
	
	void factorial_mod(){
		 fac[0] = 1;
		for(long long i = 1; i < MAX_VAL; fac[i] %= MOD, i++)
			fac[i] = fac[i - 1] * (i % MOD);
	}
	
	long long power(long long x, long long n){
		long long ans = 1;
		for(;n;n >>= 1, x *= x, ans %= MOD, x %= MOD)
			if(n&1)ans*=x;
		return ans % MOD;
	}
	
	void exgcd(long long a, long long b, long long &x, long long &y){
		if(b == 0){
			x = 1;
			y = 0;
			return ;
		}
		exgcd(b, a % b, y, x);
		y -= a / b * x;
	}
	
	void modular_multiplicatibe_inverse(){
		long long x, y;  
		exgcd(fac[MAX_VAL - 1], MOD, x, y);
		mmi[MAX_VAL-1] = (x%MOD + MOD) % MOD;
		// mmi[MAX_VAL-1] = power(fac[MAX_VAL-1], MOD-2);
		for(long long i = MAX_VAL - 2; i >= 0; mmi[i]%=MOD, i--)
			mmi[i] = mmi[i + 1] * ((i + 1) % MOD);
	}
	
	long long combination(long long n, long long r){
		return n < r ? 0 :fac[n] * (mmi[r] * mmi[n-r] % MOD) % MOD;
	}
};
	
signed main(){
	cout<<fixed<<setprecision(10);
	
	const int num = 26;
	
	binomial_coefficients BC;
	int res = 0, two;
	string S;
	vector<vector<int>> count;
	
	cin>>S;
	
	count.resize(S.size()+1, vector<int>(num));
	
	BC.init(S.size()+2);
	
	for(int i = 1; i <= S.size(); i++){
		res += i * BC.combination(S.size(), i);
	}
	
	for(int i = S.size()-1; i >= 0; i--){
		count[i][S[i] - 'a'] += (BC.power(2, (int)S.size() - i - 1)) % MOD;
		
		for(int j = 0; j < num; j++){
			count[i][j] += count[i+1][j];
			count[i][j] %= MOD;
		}
	}
	
	for(int i = 0; i < S.size(); i++){
		
		res = (res + MOD - count[i+1][S[i] - 'a']* BC.power(2, i) % MOD) %MOD;
	}
	
	cout<<res<<endl;
	
	return 0;
}