#line 1 "main.cpp"

/**
 * @title Template
 */

#include <iostream>
#include <algorithm>
#include <utility>
#include <numeric>
#include <vector>
#include <array>
#include <cassert>

#line 2 "/Users/kodamankod/Desktop/Programming/Library/other/chmin_chmax.cpp"

template <class T, class U>
constexpr bool chmin(T &lhs, const U &rhs) {
  if (lhs > rhs) { lhs = rhs; return true; }
  return false;
}

template <class T, class U>
constexpr bool chmax(T &lhs, const U &rhs) {
  if (lhs < rhs) { lhs = rhs; return true; }
  return false;
}

/**
 * @title Chmin/Chmax
 */
#line 2 "/Users/kodamankod/Desktop/Programming/Library/other/range.cpp"

#line 4 "/Users/kodamankod/Desktop/Programming/Library/other/range.cpp"

class range {
public:
  class iterator {
  private:
    int64_t M_position;

  public:
    constexpr iterator(int64_t position) noexcept: M_position(position) { }
    constexpr void operator ++ () noexcept { ++M_position; }
    constexpr bool operator != (iterator other) const noexcept { return M_position != other.M_position; }
    constexpr int64_t operator * () const noexcept { return M_position; }

  };

  class reverse_iterator {
  private:
    int64_t M_position;
  
  public:
    constexpr reverse_iterator(int64_t position) noexcept: M_position(position) { }
    constexpr void operator ++ () noexcept { --M_position; }
    constexpr bool operator != (reverse_iterator other) const noexcept { return M_position != other.M_position; }
    constexpr int64_t operator * () const noexcept { return M_position; }

  };
  
private:
  const iterator M_first, M_last;

public:
  constexpr range(int64_t first, int64_t last) noexcept: M_first(first), M_last(std::max(first, last)) { }
  constexpr iterator begin() const noexcept { return M_first; }
  constexpr iterator end() const noexcept { return M_last; }
  constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(*M_last - 1); } 
  constexpr reverse_iterator rend() const noexcept { return reverse_iterator(*M_first - 1); } 

};

/**
 * @title Range
 */
#line 2 "/Users/kodamankod/Desktop/Programming/Library/other/rev.cpp"

#include <type_traits>
#include <iterator>
#line 6 "/Users/kodamankod/Desktop/Programming/Library/other/rev.cpp"

template <class T>
class rev_impl {
public:
  using iterator = decltype(std::rbegin(std::declval<T>()));

private:
  const iterator M_begin;
  const iterator M_end;

public:
  constexpr rev_impl(T &&cont) noexcept: M_begin(std::rbegin(cont)), M_end(std::rend(cont)) { }
  constexpr iterator begin() const noexcept { return M_begin; }
  constexpr iterator end() const noexcept { return M_end; }

};

template <class T>
constexpr decltype(auto) rev(T &&cont) {
  return rev_impl<T>(std::forward<T>(cont));
}

/**
 * @title Reverser
 */
#line 2 "/Users/kodamankod/Desktop/Programming/Library/algebraic/modular.cpp"

#include <cstdint>
#line 5 "/Users/kodamankod/Desktop/Programming/Library/algebraic/modular.cpp"

template <class Modulus>
class modular {
public:
  using value_type = uint32_t;
  using cover_type = uint64_t;
  static constexpr value_type mod() { return Modulus::value(); }

  template <class T>
  static constexpr value_type normalize(T value_) noexcept {
    if (value_ < 0) {
      value_ = -value_;
      value_ %= mod();
      if (value_ == 0) return 0;
      return mod() - value_;
    }
    return value_ % mod();
  }

private:
  value_type value;

public:
  constexpr modular() noexcept : value(0) { }
  template <class T>
  explicit constexpr modular(T value_) noexcept : value(normalize(value_)) { }
  template <class T>
  explicit constexpr operator T() const noexcept { return static_cast<T>(value); }

  constexpr value_type get() const noexcept { return value; }
  constexpr value_type &extract() noexcept { return value; }
  constexpr modular operator - () const noexcept { return modular(mod() - value); }
  constexpr modular operator ~ () const noexcept { return inverse(*this); }

  constexpr modular operator + (const modular &rhs) const noexcept { return modular(*this) += rhs; }
  constexpr modular& operator += (const modular &rhs) noexcept { 
    if ((value += rhs.value) >= mod()) value -= mod(); 
    return *this; 
  }

  constexpr modular operator - (const modular &rhs) const noexcept { return modular(*this) -= rhs; }
  constexpr modular& operator -= (const modular &rhs) noexcept { 
    if ((value += mod() - rhs.value) >= mod()) value -= mod(); 
    return *this; 
  }

  constexpr modular operator * (const modular &rhs) const noexcept { return modular(*this) *= rhs; }
  constexpr modular& operator *= (const modular &rhs) noexcept { 
    value = (cover_type) value * rhs.value % mod();
    return *this;
  }

  constexpr modular operator / (const modular &rhs) const noexcept { return modular(*this) /= rhs; }
  constexpr modular& operator /= (const modular &rhs) noexcept { return (*this) *= rhs.inverse(); }

  constexpr bool zero() const noexcept { return value == 0; }
  constexpr bool operator == (const modular &rhs) const noexcept { return value == rhs.value; }
  constexpr bool operator != (const modular &rhs) const noexcept { return value != rhs.value; }

  friend std::ostream& operator << (std::ostream &stream, const modular &rhs) { return stream << rhs.value; }
  friend constexpr modular inverse(modular val) noexcept { return power(val, mod() - 2); }
  friend constexpr modular power(modular val, cover_type exp) noexcept { 
    modular res(1);
    for (; exp > 0; exp >>= 1, val *= val) if (exp & 1) res *= val;
    return res;
  }

};

template <uint32_t Val>
struct modulus_impl { static constexpr uint32_t value() noexcept { return Val; } };
template <uint32_t Val>
using mint32_t = modular<modulus_impl<Val>>;

struct runtime_mod { static uint32_t &value() noexcept { static uint32_t val = 0; return val; } };
using rmint32_t = modular<runtime_mod>;

/**
 * @title Modint
 */
#line 2 "/Users/kodamankod/Desktop/Programming/Library/algebraic/ntt.cpp"

#line 2 "/Users/kodamankod/Desktop/Programming/Library/other/bit_operation.cpp"

#include <cstddef>
#line 5 "/Users/kodamankod/Desktop/Programming/Library/other/bit_operation.cpp"

constexpr size_t   bit_ppc(const uint64_t x)   { return __builtin_popcountll(x); }
constexpr size_t   bit_ctzr(const uint64_t x)  { return x == 0 ? 64 : __builtin_ctzll(x); }
constexpr size_t   bit_ctzl(const uint64_t x)  { return x == 0 ? 64 : __builtin_clzll(x); }
constexpr size_t   bit_width(const uint64_t x) { return 64 - bit_ctzl(x); }
constexpr uint64_t bit_msb(const uint64_t x)   { return x == 0 ? 0 : uint64_t(1) << (bit_width(x) - 1); }
constexpr uint64_t bit_lsb(const uint64_t x)   { return x & (-x); }
constexpr uint64_t bit_cover(const uint64_t x) { return x == 0 ? 0 : bit_msb(2 * x - 1); }

constexpr uint64_t bit_rev(uint64_t x) {
  x = ((x >> 1) & 0x5555555555555555) | ((x & 0x5555555555555555) << 1);
  x = ((x >> 2) & 0x3333333333333333) | ((x & 0x3333333333333333) << 2);
  x = ((x >> 4) & 0x0F0F0F0F0F0F0F0F) | ((x & 0x0F0F0F0F0F0F0F0F) << 4);
  x = ((x >> 8) & 0x00FF00FF00FF00FF) | ((x & 0x00FF00FF00FF00FF) << 8);
  x = ((x >> 16) & 0x0000FFFF0000FFFF) | ((x & 0x0000FFFF0000FFFF) << 16);
  x = (x >> 32) | (x << 32);
  return x;
}

/**
 * @title Bit Operations
 */
#line 4 "/Users/kodamankod/Desktop/Programming/Library/algebraic/ntt.cpp"

#line 10 "/Users/kodamankod/Desktop/Programming/Library/algebraic/ntt.cpp"

namespace ntt_detail {

  constexpr uint32_t primitive_root(const uint32_t mod) {
    std::array<uint32_t, 32> exp{};
    uint32_t cur = mod - 1;
    size_t size = 0;
    for (uint32_t i = 2; i * i <= cur; ++i) {
      if (cur % i == 0) {
        exp[size++] = (mod - 1) / i;
        while (cur % i == 0) cur /= i;
      }
    }
    if (cur != 1) exp[size++] = (mod - 1) / cur;
    for (uint32_t check = 1; check < mod; ++check) {
      for (auto e: exp) {
        if (e == 0) return check;
        uint64_t a = check, x = 1;
        while (e > 0) {
          if (e & 1) (x *= a) %= mod;
          (a *= a) %= mod;
          e >>= 1;
        }
        if (x == 1) break;
      }
    }
    return mod;
  };

  template <size_t N, class T>
  constexpr std::array<T, N> compute_roots(T omega) {
    std::array<T, N> res;
    res[N - 1] = omega;
    for (size_t i = N - 1; i > 0; --i) {
      res[i - 1] = res[i] * res[i];
    }
    return res;
  }

}

template <class Modular>
class number_theoretic_transform {
public:
  using value_type = Modular;
  static constexpr uint32_t mod = Modular::mod();
  static constexpr uint32_t prim = ntt_detail::primitive_root(mod);

private:
  static constexpr size_t level = bit_ctzr(mod - 1);
  static constexpr value_type omega = power(value_type(prim), ((mod - 1) >> level)); 
  static constexpr auto roots = ntt_detail::compute_roots<level>(omega);
  static constexpr auto inv_roots = ntt_detail::compute_roots<level>(inverse(omega));

public:
  static void transform(std::vector<value_type> &F) {
    const size_t size = F.size();
    const size_t logn = bit_ctzr(size);
    for (size_t i = 0; i < size; ++i) {
      const size_t j = bit_rev(i) >> (64 - logn);
      if (i < j) std::swap(F[i], F[j]);
    }
    value_type coeff(1);
    for (size_t s = 0; s < logn; ++s) {
      const size_t mh = 1 << s;
      const size_t m = mh << 1;
      for (size_t i = 0; i < size; i += m) {
        coeff = value_type(1);
        for (size_t j = i; j < i + mh; ++j) {
          const auto a = F[j];
          const auto b = F[j + mh] * coeff;
          F[j] = a + b;
          F[j + mh] = a - b;
          coeff *= roots[s];
        }
      }
    }
  }

  static void inv_transform(std::vector<value_type> &F) {
    const size_t size = F.size();
    const size_t logn = bit_ctzr(size);
    for (size_t i = 0; i < size; ++i) {
      const size_t j = bit_rev(i) >> (64 - logn);
      if (i < j) std::swap(F[i], F[j]);
    }
    value_type coeff(1);
    for (size_t s = 0; s < logn; ++s) {
      const size_t mh = 1 << s;
      const size_t m = mh << 1;
      for (size_t i = 0; i < size; i += m) {
        coeff = value_type(1);
        for (size_t j = i; j < i + mh; ++j) {
          const auto a = F[j];
          const auto b = F[j + mh] * coeff;
          F[j] = a + b;
          F[j + mh] = a - b;
          coeff *= inv_roots[s];
        }
      }
    }
    coeff = inverse(value_type(size));
    for (auto &x: F) x *= coeff;
  }

};

/**
 * @title Number Theoretic Transform
 */
#line 19 "main.cpp"

using i32 = int32_t;
using i64 = int64_t;
using u32 = uint32_t;
using u64 = uint64_t;

constexpr i32 inf32 = (i32(1) << 30) - 1;
constexpr i64 inf64 = (i64(1) << 62) - 1;

using m32 = mint32_t<998244353>;
using ntt = number_theoretic_transform<m32>;

std::vector<m32> convolve(std::vector<m32> A, std::vector<m32> B) {
  if (A.empty() || B.empty()) return { };
  const size_t res_size = A.size() + B.size() - 1;
  const size_t fix_size = 1 << (31 - __builtin_clz(2 * res_size - 1));
  A.resize(fix_size);
  B.resize(fix_size);
  ntt::transform(A);
  ntt::transform(B);
  for (size_t i = 0; i < fix_size; ++i) {
    A[i] *= B[i];
  }
  ntt::inv_transform(A);
  A.resize(res_size);
  return A;
}

int main() {
  std::string S;
  std::cin >> S;
  std::array<std::vector<m32>, 26> arr;
  for (auto &v: arr) {
    v = { m32(1) };
  } 
  for (auto c: S) {
    auto &v = arr[c - 'a'];
    v.push_back(v.back() * inverse(m32(v.size())));
  }
  auto &v = arr[0];
  for (auto i: range(1, 26)) {
    v = convolve(std::move(v), arr[i]);
  }
  m32 cur(1), ans;
  for (auto i: range(0, v.size())) {
    ans += cur * v[i];
    cur *= m32(i + 1);
  }
  std::cout << ans - m32(1) << '\n';
  return 0;
}