#include <algorithm>
#include <bitset>
#include <cassert>
#include <cctype>
#include <chrono>
#define _USE_MATH_DEFINES
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iostream>
#include <iterator>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
using namespace std;

#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()

const int INF = 0x3f3f3f3f;
const long long LINF = 0x3f3f3f3f3f3f3f3fLL;
const double EPS = 1e-8;
const int MOD = 998244353;
const int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};
/*-------------------------------------------------*/
vector<long long> divisor(long long val) {
  vector<long long> res;
  for (long long i = 1; i * i <= val; ++i) {
    if (val % i == 0) {
      res.emplace_back(i);
      if (i * i != val) res.emplace_back(val / i);
    }
  }
  sort(ALL(res));
  return res;
}

int mod = MOD;
struct ModInt {
  unsigned val;
  ModInt(): val(0) {}
  ModInt(long long x) : val(x >= 0 ? x % mod : x % mod + mod) {}
  ModInt pow(long long exponent) {
    ModInt tmp = *this, res = 1;
    while (exponent > 0) {
      if (exponent & 1) res *= tmp;
      tmp *= tmp;
      exponent >>= 1;
    }
    return res;
  }
  ModInt &operator+=(const ModInt &rhs) { if((val += rhs.val) >= mod) val -= mod; return *this; }
  ModInt &operator-=(const ModInt &rhs) { if((val += mod - rhs.val) >= mod) val -= mod; return *this; }
  ModInt &operator*=(const ModInt &rhs) { val = (unsigned long long)val * rhs.val % mod; return *this; }
  ModInt &operator/=(const ModInt &rhs) { return *this *= rhs.inv(); }
  bool operator==(const ModInt &rhs) const { return val == rhs.val; }
  bool operator!=(const ModInt &rhs) const { return val != rhs.val; }
  bool operator<(const ModInt &rhs) const { return val < rhs.val; }
  bool operator<=(const ModInt &rhs) const { return val <= rhs.val; }
  bool operator>(const ModInt &rhs) const { return val > rhs.val; }
  bool operator>=(const ModInt &rhs) const { return val >= rhs.val; }
  ModInt operator-() const { return ModInt(-val); }
  ModInt operator+(const ModInt &rhs) const { return ModInt(*this) += rhs; }
  ModInt operator-(const ModInt &rhs) const { return ModInt(*this) -= rhs; }
  ModInt operator*(const ModInt &rhs) const { return ModInt(*this) *= rhs; }
  ModInt operator/(const ModInt &rhs) const { return ModInt(*this) /= rhs; }
  friend ostream &operator<<(ostream &os, const ModInt &rhs) { return os << rhs.val; }
  friend istream &operator>>(istream &is, ModInt &rhs) { long long x; is >> x; rhs = ModInt(x); return is; }
private:
  ModInt inv() const {
    // if (__gcd(static_cast<int>(val), mod) != 1) assert(false);
    unsigned a = val, b = mod; int x = 1, y = 0;
    while (b) {
      unsigned tmp = a / b;
      swap(a -= tmp * b, b);
      swap(x -= tmp * y, y);
    }
    return ModInt(x);
  }
};
ModInt abs(const ModInt &x) { return x.val; }
struct Combinatorics {
  Combinatorics(int MAX = 5000000) {
    MAX <<= 1;
    fact.resize(MAX + 1);
    fact_inv.resize(MAX + 1);
    fact[0] = 1;
    FOR(i, 1, MAX + 1) fact[i] = fact[i - 1] * i;
    fact_inv[MAX] = ModInt(1) / fact[MAX];
    for (int i = MAX; i > 0; --i) fact_inv[i - 1] = fact_inv[i] * i;
  }
  ModInt nCk(int n, int k) {
    if (n < 0 || n < k || k < 0) return ModInt(0);
    return fact[n] * fact_inv[k] * fact_inv[n - k];
  }
  ModInt nPk(int n, int k) {
    if (n < 0 || n < k || k < 0) return ModInt(0);
    return fact[n] * fact_inv[n - k];
  }
  ModInt nHk(int n, int k) {
    if (n < 0 || k < 0) return ModInt(0);
    return (k == 0 ? ModInt(1) : nCk(n + k - 1, k));
  }
private:
  vector<ModInt> fact, fact_inv;
};

int main() {
  cin.tie(nullptr); ios::sync_with_stdio(false);
  // freopen("input.txt", "r", stdin);

  int n; string s; cin >> n >> s;
  vector<long long> d = divisor(n);
  d.pop_back();
  vector<int> len;
  for (int e : d) if ((n / e) & 1) {
    len.emplace_back(e);
  }
  int sz = len.size();
  vector<ModInt> dp(sz, 0);
  REP(i, sz) {
    string mx = "", mx_rev = "";
    REP(j, len[i]) {
      mx += s[j];
      mx_rev += (s[j] == '0' ? '1' : '0');
    }
    bool ok = true, rev = true;
    for (int j = len[i]; j < n; j += len[i]) {
      string here = s.substr(j, len[i]);
      if (rev) {
        if (mx_rev < here) {
          break;
        } else if (mx_rev > here) {
          ok = false;
          break;
        }
      } else {
        if (mx < here) {
          break;
        } else if (mx > here) {
          ok = false;
          break;
        }
      }
      rev = !rev;
    }
    ModInt mx_val = 1, now = 1;
    for (int j = len[i] - 1; j >= 0; --j) {
      mx_val += now * (mx[j] - '0');
      now *= 2;
    }
    if (!ok) mx_val -= 1;
    dp[i] += mx_val;
    FOR(j, i + 1, sz) {
      if (len[j] % len[i] == 0) dp[j] -= dp[i];
    }
  }
  ModInt s_val = 1, now = 1;
  for (int i = n - 1; i >= 0; --i) {
    s_val += now * (s[i] - '0');
    now *= 2;
  }
  REP(i, sz) s_val -= dp[i];
  ModInt ans = s_val * n * 2;
  REP(i, sz) ans += dp[i] * len[i] * 2;
  cout << ans << '\n';
  return 0;

  // int n = 6;
  // REP(i, 1 << n) {
  //   bitset<6> bit(i);
  //   string ans = bit.to_string();
  //   set<string> st;
  //   st.emplace(ans);
  //   string now = ans;
  //   int cnt = 0;
  //   while (true) {
  //     ++cnt;
  //     if (now.back() == '0') {
  //       for (int i = n - 1; i >= 1; --i) now[i] = now[i - 1];
  //       now[0] = '1';
  //     } else {
  //       for (int i = n - 1; i >= 1; --i) now[i] = now[i - 1];
  //       now[0] = '0';
  //     }
  //     if (st.count(now)) break;
  //     st.emplace(now);
  //   }
  //   if (ans != now) cnt = 0;
  //   // if (cnt != 2 * n) cout << i << ' ' << cnt << '\n';
  //   if (cnt != 2 * n) cout << bit << ' ' << cnt << '\n';
  // }
}


Measured memory_bytes: 788