#include <bits/stdc++.h>
using namespace std;
const int mod = (int)1e9 + 7;
int add(int a, int b) {
  long long c = (long long)a + b;
  while (c < 0) c += mod;
  return c % mod;
}
int mult(int a, int b) {
  long long c = (long long)a * b;
  return c % mod;
}
const int MAXN = 1010;
int Bell[MAXN];
void computeBell() {
  vector<int> v;
  v.push_back(1);
  for (int i = 0; i < MAXN; i++) {
    Bell[i] = v[0];
    vector<int> vi;
    vi.push_back(v.back());
    for (int j : v) {
      vi.push_back(add(vi.back(), j));
    }
    v = vi;
  }
}
int m, n;
vector<string> v(MAXN, "");
char s[MAXN];
void load() {
  scanf("%d%d", &m, &n);
  for (int i = 0; i < n; i++) {
    scanf("%s", s);
    for (int j = 0; j < m; j++) v[j] = v[j] + s[j];
  }
}
void solve() {
  computeBell();
  int sol = 1;
  sort(v.begin(), v.begin() + m);
  string cur = "";
  int br = 1;
  for (string s : v) {
    if (s == cur) {
      ++br;
    } else {
      sol = mult(sol, Bell[br]);
      cur = s;
      br = 1;
    }
  }
  printf("%d\n", sol);
}
int main() {
  load();
  solve();
  return 0;
}
