#include <iostream>
#include <cstdio>
#include <string>
#include <algorithm>
#include <utility>
#include <cmath>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <tuple>
#include <numeric>
#include <functional>
#include <atcoder/convolution>
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef vector<ll> vl;
typedef vector<vector<ll>> vvl;
typedef pair<ll, ll> P;
#define rep(i, n) for(ll i = 0; i < n; i++)
#define exrep(i, a, b) for(ll i = a; i <= b; i++)
#define out(x) cout << x << endl
#define exout(x) printf("%.10f\n", x)
#define chmax(x, y) x = max(x, y)
#define chmin(x, y) x = min(x, y)
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define pb push_back
#define re0 return 0
const ll mod = 998244353;
const ll INF = 1e16;
 
const ll MAX = 300010;
 
ll fact[MAX];  // fact[i] : iの階乗のmod
ll inv[MAX];  // inv[i] : iの逆数のmod
ll invfact[MAX];  // invfact[i] : iの階乗の逆数のmod
 
void init() {
    fact[0] = 1;
    inv[0] = inv[1] = 1;
    invfact[0] = 1;
    for(ll i = 1; i < MAX; i++) {
        fact[i] = i * fact[i-1] % mod;
        if(i >= 2) {
            inv[i] = mod - inv[mod % i] * (mod / i) % mod;
        }
        invfact[i] = invfact[i-1] * inv[i] % mod;
    }
}
 
int main() {
    string s;
    cin >> s;
    ll n = s.size();
    
    init();
    
    vl a(26);
    for(char c : s) {
        a[(ll)(c - 'a')]++;
    }

    vvl dp(27, vl(n+1));  // dp[i][j] : iまでで、j個使うときの場合の数
    dp[0][0] = 1;
    rep(i, 26) {
        vl f(n+1);
        exrep(j, 0, a[i]) {
            f[j] = invfact[j];
        }
        vl g(n+1);
        exrep(j, 0, n) {
            g[j] = dp[i][j] * invfact[j] % mod;
        }
        vl h = convolution<mod>(f, g);
        exrep(j, 0, n) {
            dp[i+1][j] = fact[j] * h[j] % mod;
        }
    }
    
    ll ans = 0;
    exrep(j, 1, n) {
        ans += dp[26][j];
        ans %= mod;
    }
    
    out(ans);
    re0;
}