#include <bits/stdc++.h>
#define be(v) (v).begin(),(v).end()
#define pb(q) push_back(q)
typedef long long ll;
using namespace std;
const ll mod=998244353, INF=mod*mod*3LL;
#define doublecout(a) cout<<fixed<<setprecision(10)<<a<<endl;

long long modpow(long long a, long long n) {
    long long res = 1;
    while (n > 0) {
        if (n & 1) res = res * a % mod;
        a = a * a % mod;
        n >>= 1;
    }
    return res;
}


int main() {
    cin.tie(0);
    cout.tie(0);
    ios::sync_with_stdio(false);
    int N;
    string X;
    cin >> N >> X;
    vector<ll> f(N+1);
	for(int k=1;k<=N;k+=2)if(N%k==0){
		int L=N/k;
		bool fl=1;
		for(int i=0; i < N && fl ;i++){
			if(X[i]=='1'){
				if(i < L || X[i-L] == '1'){
					(f[L] += (i < L)? modpow(2LL,L-i-1): 1LL) %= mod;
				}
			}
			if(i >= L && X[i] == X[i-L]) fl = 0;
		}
		if(fl) (f[L] += 1) %= mod;
	}
	int ans=0;
	for(int i=1;i<=N;i++) if(N % i == 0 && N / i % 2 == 1 && f[i]){
		(ans += (f[i] * i * 2)%mod ) %= mod;
		for(int j=i*2;j<=N;j+=i) (f[j] -= f[i]) %= mod;
	}
    cout << (ans + mod) % mod << endl;
    return 0;
}
