#if __has_include("../library/Basic/Debug.hpp")

#include "../library/Basic/Debug.hpp"

#else

/* ----- Header Files ----- */
// IO
#include <cstdio>
#include <iomanip>
#include <ios>
#include <iostream>

// algorithm
#include <algorithm>
#include <cmath>
#include <numeric>

// container
#include <vector>
#include <array>
#include <string>
#include <tuple>
#include <complex>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <bitset>

// others
#include <random>
#include <limits>
#include <functional>
#include <ctime>
#include <cassert>
#include <cstdint>

/* ----- Type Alias ----- */
using Int = long long int;
using Real = long double;
using std::array;
using std::pair;
using std::string;
using std::tuple;
using std::vector;
template <class T>
using MaxHeap = std::priority_queue<T>;
template <class T>
using MinHeap = std::priority_queue<T, std::vector<T>, std::greater<T>>;

template <class T>
T genv(T v) { return v; }

template <class T, class... Ts>
auto genv(size_t l, Ts... ts) {
    return vector<decltype(genv<T>(ts...))>(l, genv<T>(ts...));
}

template <class Cost = Int>
struct Edge {
    Int src, dst;
    Cost cost;
    Edge(Int src = -1, Int dst = -1, Cost cost = 1)
        : src(src), dst(dst), cost(cost){};

    bool operator<(const Edge<Cost>& e) const { return this->cost < e.cost; }
    bool operator>(const Edge<Cost>& e) const { return this->cost > e.cost; }
};

template <class Cost = Int>
using Edges = vector<Edge<Cost>>;
template <class Cost = Int>
using Graph = vector<vector<Edge<Cost>>>;

#endif

/* ----- Misc ----- */
void fastio() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
}

struct Fout {
    Int precision;
    explicit Fout(Int precision) : precision(precision) {}
};

std::ostream& operator<<(std::ostream& os, const Fout& fio) {
    os << std::fixed << std::setprecision(fio.precision);
    return os;
}

template <int MOD>
class ModInt {
    using lint = long long;

public:
    int val;

    // constructor
    ModInt(lint v = 0) : val(v % MOD) {
        if (val < 0) val += MOD;
    };

    // assignment
    ModInt& operator=(const ModInt& x) {
        if (this != &x) { this->val = x.val; }
        return *this;
    }

    // unary operator
    ModInt operator+() const { return ModInt(val); }
    ModInt operator-() const { return ModInt(MOD - val); }
    ModInt operator~() const { return *this ^ (MOD - 2); }

    // increment / decrement
    ModInt& operator++() { return *this += 1; }
    ModInt& operator--() { return *this -= 1; }
    ModInt operator++(int) {
        ModInt before = *this;
        ++(*this);
        return before;
    }
    ModInt operator--(int) {
        ModInt before = *this;
        --(*this);
        return before;
    }

    // arithmetic
    ModInt operator+(const ModInt& x) const { return ModInt(*this) += x; }
    ModInt operator-(const ModInt& x) const { return ModInt(*this) -= x; }
    ModInt operator*(const ModInt& x) const { return ModInt(*this) *= x; }
    ModInt operator%(const ModInt& x) const { return ModInt(*this) %= x; }
    ModInt operator/(const ModInt& x) const { return ModInt(*this) /= x; }
    ModInt operator^(const ModInt& x) const { return ModInt(*this) ^= x; }

    // compound assignment
    ModInt& operator+=(const ModInt& x) {
        if ((val += x.val) >= MOD) val -= MOD;
        return *this;
    }
    ModInt& operator-=(const ModInt& x) {
        if ((val -= x.val) < 0) val += MOD;
        return *this;
    }
    ModInt& operator*=(const ModInt& x) {
        val = lint(val) * x.val % MOD;
        return *this;
    }
    ModInt& operator%=(const ModInt& x) {
        val %= x.val;
        return *this;
    }
    ModInt& operator/=(const ModInt& x) { return *this *= ~x; }
    ModInt& operator^=(const ModInt& x) {
        int n = x.val;
        ModInt b = *this;
        if (n < 0) n = -n, b = ~b;

        *this = 1;
        while (n > 0) {
            if (n & 1) *this *= b;
            n >>= 1;
            b *= b;
        }
        return *this;
    }

    // compare
    bool operator==(const ModInt& b) const { return val == b.val; }
    bool operator!=(const ModInt& b) const { return val != b.val; }
    bool operator<(const ModInt& b) const { return val < b.val; }
    bool operator<=(const ModInt& b) const { return val <= b.val; }
    bool operator>(const ModInt& b) const { return val > b.val; }
    bool operator>=(const ModInt& b) const { return val >= b.val; }

    // I/O
    friend std::ostream& operator<<(std::ostream& os, const ModInt& x) noexcept { return os << x.val; }
    friend std::istream& operator>>(std::istream& is, ModInt& x) noexcept { return is >> x.val; }
};

/* ----- Constants ----- */
// constexpr Int INF = std::numeric_limits<Int>::max() / 3;
constexpr Int MOD = 998244353;
// const Real PI = acos(-1);
// constexpr Real EPS = 1e-10;
// std::mt19937 mt(int(std::time(nullptr)));

using mint = ModInt<MOD>;

mint convert(const string& s) {
    mint ret = 0;
    for (char c : s) {
        ret = (ret * 2) + (c == '1');
    }
    return ret;
}

int main() {
    int n;
    string s;
    std::cin >> n >> s;

    int e;
    for (e = 25; e > 0; --e) {
        if (n % (1 << e) == 0) break;
    }

    vector<mint> cnt(n + 1, 0);
    for (int l = 1; l <= n; ++l) {
        if (l % (1 << e) != 0 || n % l != 0) continue;

        string head = s.substr(0, l);

        auto& c = cnt[l];
        c = convert(head);

        while (head.length() < s.length()) {
            int prev = head[head.length() - l] - '0';
            head.push_back(1 - prev + '0');
        }
        if (head <= s) ++c;

        for (int sl = 1; sl < l; ++sl) {
            if (l % sl == 0) c -= cnt[sl];
        }
    }

    mint ans = 0;
    for (int l = 1; l <= n; ++l) {
        if (cnt[l] == 0) continue;
        ans += cnt[l] * l * 2;
    }

    std::cout << ans << std::endl;
    return 0;
}


Measured memory_bytes: 1868