#include <bits/stdc++.h>
using namespace std;
template <typename T>
T gcd(T first, T second) {
  while (second > 0) {
    first %= second;
    swap(first, second);
  }
  return first;
}
template <class T>
T lcm(T a, T b) {
  return a / gcd(a, b) * b;
}
template <class _T>
inline _T sqr(const _T &first) {
  return first * first;
}
template <class _T>
inline string tostr(const _T &a) {
  ostringstream os("");
  os << a;
  return os.str();
}
const long double PI = 3.1415926535897932384626433832795L;
template <typename T>
inline void input(T &a) {
  static int ed;
  a = 0;
  while (!isdigit(ed = getchar()) && ed != '-') {
  }
  char neg = 0;
  if (ed == '-') {
    neg = 1;
    ed = getchar();
  }
  while (isdigit(ed)) {
    a = 10 * a + ed - '0';
    ed = getchar();
  }
  if (neg) a = -a;
}
template <typename T = int>
inline T nxt() {
  T res;
  input(res);
  return res;
}
mt19937 generator;
bool check(int v) {
  if (v < 2) return false;
  for (int i = 2; i * i <= v; ++i) {
    if (v % i == 0) {
      return false;
    }
  }
  return true;
}
long long pw(long long a, long long n, long long m) {
  long long res = 1;
  while (n) {
    if (n & 1ll) {
      res = res * a % m;
    }
    a = a * a % m;
    n >>= 1;
  }
  return res;
}
long long bin[5][5];
void pre() {
  for (int i = 0; i < 5; ++i) {
    bin[i][0] = 1;
    for (int j = 1; j <= i; ++j) {
      bin[i][j] = bin[i - 1][j] + bin[i - 1][j - 1];
    }
  }
}
void read() {}
void test() {}
long long mod = 1000000007;
vector<int> g[1 << 20];
int dp[1 << 20];
int solve(int v) {
  int &res = dp[v];
  if (res != -1) {
    return res;
  }
  res = 1;
  for (int to : g[v]) {
    if (to < v) {
      res = max(res, solve(to) + 1);
    }
  }
  return res;
}
void solve() {
  int n = nxt();
  int m = nxt();
  for (int i = 0; i < m; ++i) {
    int u = nxt() - 1;
    int v = nxt() - 1;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  memset(dp, 255, sizeof(dp));
  long long ans = 0;
  for (int i = 0; i < n; ++i) {
    ans = max(ans, 1ll * solve(i) * (int)g[i].size());
  }
  cout << ans << endl;
}
void solve2() {}
int main() {
  int t = 1;
  pre();
  while (t--) {
    read();
    solve();
  }
  return 0;
}
