#include<cstdio>
#include<cstring>
const long long mod = 1e9+7;
char s[200005];
long long f[200005][28];

long long power(long long a,long long b){
    long long res = 1;
    while(b){
        if(b&1) res = res*a%mod;
        a = a*a%mod;
        b /= 2;
    }
    return res;
}

int main(){
    scanf("%s",s+1);
    int n = strlen(s+1);
    long long ans = 0;
    f[0][0] = 1;
    for(int i = 1; i <= 26; i++) f[0][i] = 0;
    long long sum = f[0][0];
    for(int i = 1; i <= n; i++){
        int u = s[i]-'a'+1;
        long long newSum = 0;
        for(int j = 0; j <= 26; j++){
            if(j==u) f[i][j] = (f[i-1][j]+sum)%mod;
            else f[i][j] = f[i-1][j];
            newSum += f[i][j]; if(newSum>=mod) newSum -= mod;
        }
        long long way = sum-f[i-1][u];
        if(way<0) way += mod;
        long long add = way*power(2,n-i)%mod;
        //printf("way = %lld, sum = %lld\n",way,sum);
        ans += add; if(ans>=mod) ans -= mod;
        sum = newSum;
    }
    printf("%lld\n",ans);
    return 0;
}