#include <bits/stdc++.h>

using namespace std;
using vi = vector<int>;
#define int long long
#define rep(i, n) for (int i = 0; i < n; i++)
#define rer(i, n) for (int i = n; i >= 0; i--)
#define sz(a) (int)a.size()


int MOD = 998244353;
struct mint {
    int x;
    mint() : x(0) {}
    mint(int a) {
        x = a % MOD;
        if (x < 0) x += MOD;
    }
    mint &operator+=(mint that) {
        x = (x + that.x) % MOD;
        return *this;
    }
    mint &operator-=(mint that) {
        x = (x + MOD - that.x) % MOD;
        return *this;
    }
    mint &operator*=(mint that) {
        x = (int) x * that.x % MOD;
        return *this;
    }
    mint &operator/=(mint that) { return *this *= that.inverse(); }
    mint operator-() { return mint(-this->x); }
    friend ostream &operator<<(ostream &out, mint m) { return out << m.x; }
    mint inverse() {
        int a = x, b = MOD, u = 1, v = 0;
        while (b) {
            int t = a / b;
            a -= t * b;
            u -= t * v;
            swap(a, b);
            swap(u, v);
        }
        return mint(u);
    }
    operator int() const { return x; }
    template<class T> mint &operator+=(T that) { return operator+=((mint) that); }
    template<class T> mint &operator-=(T that) { return operator-=((mint) that); }
    template<class T> mint &operator*=(T that) { return operator*=((mint) that); }
    template<class T> mint &operator/=(T that) { return operator/=(that); }
    mint operator+(mint that) { return mint(*this) += that; }
    mint operator-(mint that) { return mint(*this) -= that; }
    mint operator*(mint that) { return mint(*this) *= that; }
    mint operator/(mint that) { return mint(*this) /= that; }
    template<class T> mint operator+(T that) { return mint(*this) += (mint) that; }
    template<class T> mint operator-(T that) { return mint(*this) -= (mint) that; }
    template<class T> mint operator*(T that) { return mint(*this) *= (mint) that; }
    template<class T> mint operator/(T that) { return mint(*this) /= (mint) that; }
    bool operator==(mint that) const { return x == that.x; }
    bool operator!=(mint that) const { return x != that.x; }
    bool operator<(mint that) const { return x < that.x; }
    bool operator<=(mint that) const { return x <= that.x; }
    bool operator>(mint that) const { return x > that.x; }
    bool operator>=(mint that) const { return x >= that.x; }
};
typedef vector<mint> vm;
template<typename T, typename U> mint mpow(const T a, const U b) {
    assert(b >= 0);
    int x = a, res = 1;
    U p = b;
    while (p > 0) {
        if (p & 1) (res *= x) %= MOD;
        (x *= x) %= MOD;
        p >>= 1;
    }
    return res;
}
using vm = vector<mint>;



//aをbit列と見なし反転
string operator~(string &a) {
    string res = a;
    for (auto &&c:res) {
        if (c == '0')c = '1';
        else if (c == '1')c = '0';
        else {
            cerr << "cant ~" << a << "must bit" << endl;
            exit(0);
        }
    }
    return res;
}

vi divisors(int v) {
    vi res;
    double lim = std::sqrt(v);
    for (int i = 1; i <= lim; ++i) { if (v % i == 0) { res.push_back(i);/*                if (i != v / i)res.push_back(v / i);*/            }}
    for (int i = sz(res) - 1; i >= 0; i--) { if (res[i] != v / res[i])res.push_back(v / res[i]); }
    return res;
}
constexpr int bsetlen = 202020;
bool operator<(bitset<bsetlen> &a, bitset<bsetlen> &b) {rer(i, bsetlen - 1) {if (a[i] < b[i])return true;if (a[i] > b[i])return false;}return false;}
bool operator>(bitset<bsetlen> &a, bitset<bsetlen> &b) {rer(i, bsetlen - 1) {if (a[i] > b[i])return true;if (a[i] < b[i])return false;}return false;}
bool operator<=(bitset<bsetlen> &a, bitset<bsetlen> &b) {rer(i, bsetlen - 1) {if (a[i] < b[i])return true;if (a[i] > b[i])return false;}return true;}
bool operator>=(bitset<bsetlen> &a, bitset<bsetlen> &b) {rer(i, bsetlen - 1) {if (a[i] > b[i])return true;if (a[i] < b[i])return false;}return true;}


signed main() {
    int N;
    string X;
    cin >> N >> X;
    //Kを操作回数として扱っている
    vi K;
    {
        auto D = divisors(N * 2);
        for (auto &&k: D) {
            if ((k % 2) == 0)K.push_back(k);//kは偶数でN*2の約数
        }
    }
    int lim = N * 2 + 1;
    vector<mint> cou(lim);//周期が[k]となるような物の数
    mint res = 0;

    bitset<bsetlen> bx(X);
    for (auto &&k:K) {
        mint part = 0;
        //先頭k/2桁を決めれば後は一意に定まる
        //先頭k/2桁の自明に小さい取り方を数える
        rep(i, k / 2) {
            if (X[i] == '1')part += mpow(2, k / 2 - 1 - i);
        }
        {
            string tail = X.substr(0, k / 2);
            string head = ~tail;//mainの上

            string tx = tail;
            string sk = head+tail;
            //size
            while (sz(tx) < N) tx += sk;
            if (sz(tx) != N)continue; //予防だが使われない txのサイズは必ずN
            bitset<bsetlen> btx(tx);
            if (bx >= btx) part += 1;
        }
        cou[k] += part;
        res += cou[k] * k;
        for (int s = k * 2; s < lim; s += k) {
            cou[s] -= cou[k];//周期kはkの倍数sでも数えられるため引いておく
        }
    }
    cout << res << endl;
    return 0;
}

Measured memory_bytes: 4544