#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <string>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <iomanip>
#include <utility>
#include <tuple>
#include <functional>
#include <bitset>
#include <cassert>
#include <complex>
#include <stdio.h>
#include <time.h>
#include <numeric>
#include <random>
#include <unordered_map>
#include <unordered_set>
#define all(a) a.begin(),a.end()
#define rep(i, n) for (ll i = 0; i < (n); i++)
#define pb push_back
#define debug(x) cerr << __LINE__ << ' ' << #x << ':' << x << '\n'
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll, ll> P;
typedef complex<ld> com;
constexpr int inf = 1000000010;
constexpr ll INF = 1000000000000000010;
constexpr ld eps = 1e-12;
constexpr ld pi = 3.141592653589793238;
template<class T, class U> inline bool chmax(T &a, const U &b) { if (a < b) { a = b; return true; } return false; }
template<class T, class U> inline bool chmin(T &a, const U &b) { if (a > b) { a = b; return true; } return false; }

constexpr ll mod = 998244353;
constexpr ll root = 3;
vector<ll> fac, inv, facinv;

void modcalc(int n) {
	fac.resize(n); inv.resize(n); facinv.resize(n);
	fac[0] = 1; fac[1] = 1; inv[1] = 1;
	facinv[0] = 1; facinv[1] = 1;
	for (ll i = 2; i < n; i++) {
		fac[i] = fac[i - 1] * i % mod;
		inv[i] = mod - inv[mod % i] * (mod / i) % mod;
		facinv[i] = facinv[i - 1] * inv[i] % mod;
	}
}

ll modinv(ll a) {
	a %= mod;
	if (a == 0) abort();
	if (a < (ll)inv.size()) return inv[a];
	ll b = mod, u = 1, v = 0;
	while (b) {
		ll t = a / b;
		a -= t * b; swap(a, b);
		u -= t * v; swap(u, v);
	}
	u %= mod;
	if (u < 0) u += mod;
	return u;
}

ll modpow(ll a, ll b, ll m = mod) {
	ll ans = 1;
	a %= m;
	while (b) {
		if (b & 1) ans = ans * a % m;
		a = a * a % m;
		b >>= 1;
	}
	return ans;
}

ll modcomb(ll n, ll k) {
	if (n < 0 || k < 0 || n < k) return 0;
	return fac[n] * facinv[k] % mod * facinv[n - k] % mod;
}

ll modperm(ll n, ll k) {
	if (n < 0 || k < 0 || n < k) return 0;
	return fac[n] * facinv[n - k] % mod;
}

ll modhom(ll n, ll k) {
	if (n < 0 || k < 0 || n == 0 && k > 0) return 0;
	if (n == 0 && k == 0) return 1;
	return fac[n + k - 1] * facinv[k] % mod * facinv[n - 1] % mod;
}

void ntt(vector<ll> &f, bool inv) {
	int n = f.size();
	int h = modpow(root, (mod - 1) / n, mod);
	if (inv) h = modinv(h);
	for (int i = 0, j = 1; j < n - 1; ++j) {
		for (int k = n >> 1; k > (i ^= k); k >>= 1);
		if (j < i) swap(f[i], f[j]);
	}
	for (int i = 1, j = 2; i < n; i *= 2, j *= 2) {
		ll w = 1, base = modpow(h, n / j, mod);
		for (int k = 0; k < i; ++k, (w *= base) %= mod) {
			for (int l = k; l < n; l += j) {
				ll u = f[l];
				ll d = f[l + i] * w % mod;
				f[l] = u + d;
				if (f[l] >= mod) f[l] -= mod;
				f[l + i] = u - d;
				if (f[l + i] < 0) f[l + i] += mod;
			}
		}
	}
	for (ll &x : f) if (x < 0) x += mod;
}

vector<ll> convolution(vector<ll> f, vector<ll> g) {
	int n = 1;
	while (n < f.size() + g.size() + 2) n <<= 1;
	f.resize(n); g.resize(n);
	ntt(f, false); ntt(g, false);
	vector<ll> res(n);
	for (int i = 0; i < n; i++) res[i] = f[i] * g[i] % mod;
	ntt(res, true);
	ll inv = modinv(n);
	for (int i = 0; i < n; i++) res[i] = res[i] * inv % mod;
	return res;
}

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	cout << fixed << setprecision(20);
	modcalc(500010);

	string s;
	cin >> s;
	vector<int> cnt(26);
	for (char c : s) cnt[c - 'a']++;
	vector<ll> f(1, 1);
	rep(i, 26) {
		int sz = cnt[i] + 1;
		vector<ll> v(sz);
		rep(j, sz) v[j] = facinv[j];
		f = convolution(f, v);
		int re = 1;
		rep(j, i + 1) re += cnt[j];
		f.resize(re);
	}
	ll ans = 0;
	for (int i = 1; i <= s.size(); i++) {
		ans += f[i] * fac[i];
		ans %= mod;
	}
	cout << ans << '\n';
}