#include<cstdio>

#include<cctype>

#include<algorithm>

using namespace std;

#define rep(i,s,t) for(int i=s;i<=t;i++)

#define dwn(i,s,t) for(int i=s;i>=t;i--)

#define clr(x,c) memset(x,c,sizeof(x))

#define ll long long

const int inf=0x7f7f7f7f;

const int mod=1e9+7;

ll pw(ll a,ll b){

	ll ans=(a%=mod);--b;

	while(b){

		if(b&1) ans=ans*a%mod;

		a=a*a%mod;b>>=1;

	}

	return ans;

}

int main(){

	freopen("sets.in","r",stdin);freopen("sets.out","w",stdout);

	ll n,k;scanf("%lld%lld",&n,&k);

	if(k==1) puts("1");

	else printf("%lld\n",pw(pw(2,k)-1+mod,n));

	fclose(stdin);fclose(stdout);

	return 0;

}

#include<cstdio>

#include<cstring>

#include<cctype>

#include<algorithm>

using namespace std;

#define rep(i,s,t) for(int i=s;i<=t;i++)

#define dwn(i,s,t) for(int i=s;i>=t;i--)

#define clr(x,c) memset(x,c,sizeof(x))

#define ll long long

int read(){

	int x=0;char c=getchar();

	while(!isdigit(c)) c=getchar();

	while(isdigit(c)) x=x*10+c-'0',c=getchar();

	return x;

}

const int inf=0x7f7f7f7f;

const int nmax=1e5+5;

ll f[nmax];int t[nmax],ans[nmax];bool vis[nmax];

bool check(int x,int y){

	while(x){

		if(x%10!=4&&x%10!=7) return 0;

		x/=10;

	}

	while(y){

		if(y%10!=4&&y%10!=7) return 0;

		y/=10;

	}

	return 1;

}

int main(){

	freopen("permutation.in","r",stdin);freopen("permutation.out","w",stdout);

	f[1]=1;f[2]=1;rep(i,3,20) f[i]=f[i-1]*(i-1);

	t[1]=4;t[2]=7;int cur=0,cnt=2;

	rep(i,1,8){

		rep(j,cur+1,cur+(1<<i)) t[++cnt]=t[j]*10+4,t[++cnt]=t[j]*10+7;

		cur+=(1<<i);

	}

	int n=read(),k=read();

	if(n<=18&&k>f[n+1]||!k) puts("-1");

	else{

		--k;

		for(cur=1;cur<=n+1;++cur) if(k<f[cur]) break;--cur;

		dwn(i,cur,1){

			int tmp=k/f[i]+1,pos=0;k%=f[i];

			rep(j,1,cur) if(!vis[j]){

				if(++pos==tmp) {

					pos=j;vis[j]=1;break;

				}

			}

			ans[cur-i+1]=pos;

		}

		int res=0;

		rep(i,1,cnt) if(t[i]>n-cur) break;else res++;

		rep(i,1,cur) if(check(n-cur+i,n-cur+ans[i])) res++;

		printf("%d\n",res);

	}

	fclose(stdin);fclose(stdout);

	return 0;

}