#include <iostream>
#include <algorithm>
#include <vector>
#include <set>

typedef long long ll;
typedef double lf;

// #define DEBUG 1
struct IO
{
    #define MAXSIZE (1 << 20)
    #define isdigit(x) (x >= '0' && x <= '9')
    char buf[MAXSIZE], *p1, *p2;
    char pbuf[MAXSIZE], *pp;
    #if DEBUG
    #else
    IO() : p1(buf), p2(buf), pp(pbuf) {}
    ~IO() {fwrite(pbuf, 1, pp - pbuf, stdout);}
    #endif
    #define gc() (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, MAXSIZE, stdin), p1 == p2) ? ' ' : *p1++)
    #define blank(x) (x == ' ' || x == '\n' || x == '\r' || x == '\t')

    template <typename T>
    void Read(T &x)
    {
        #if DEBUG
        std::cin >> x;
        #else
        bool sign = 0; char ch = gc(); x = 0;
        for (; !isdigit(ch); ch = gc())
            if (ch == '-') sign = 1;
        for (; isdigit(ch); ch = gc()) x = x * 10 + (ch ^ 48);
        if (sign) x = -x;
        #endif
    }
    void Read(char *s)
    {
        #if DEBUG
        std::cin >> s;
        #else
        char ch = gc();
        for (; blank(ch); ch = gc());
        for (; !blank(ch); ch = gc()) *s++ = ch;
        *s = 0;
        #endif
    }
    void Read(char &c) {for (c = gc(); blank(c); c = gc());}

    void Push(const char &c)
    {
        #if DEBUG
        putchar(c);
        #else
        if (pp - pbuf == MAXSIZE) fwrite(pbuf, 1, MAXSIZE, stdout), pp = pbuf;
        *pp++ = c;
        #endif
    }
    template <typename T>
    void Write(T x)
    {
        if (x < 0) x = -x, Push('-');
        static T sta[35];
        int top = 0;
        do sta[top++] = x % 10, x /= 10; while (x);
        while (top) Push(sta[--top] ^ 48);
    }
    template <typename T>
    void Write(T x, char lst) {Write(x), Push(lst);}
} IO;
#define Read(x) IO.Read(x)
#define Write(x, y) IO.Write(x, y)
#define Put(x) IO.Push(x)

using namespace std;

const int MAXN = 5e5 + 10, mod = 1e9 + 7;

inline ll Qpow(ll x, ll y) { ll res = 1; while (y) (y & 1) && (res = res * x % mod), x = x * x % mod, y >>= 1; return res; }
inline void add(int &x, int y) { (x += y) >= mod && (x -= mod); }
inline int adu(int x, int y) { return (x += y) >= mod ? x - mod : x; }
inline int sbu(int x, int y) { return (x -= y) < 0 ? x + mod : x; }

int n, m;

struct inter
{
    int l, r; bool tp;
}a[MAXN];

vector <int> vec[MAXN];
set <pair <int, int>, greater <pair <int, int>>> st[2];
int f[26], g[26][MAXN];

int main()
{
    #if DEBUG
    #else
    ios::sync_with_stdio(0), cin.tie(0);
    #endif
    Read(n), Read(m);
    for (int i = 1, x, y; i <= m; i++)
    {
        Read(x), Read(y);
        if (x < y) a[i] = {x, y, 1};
        else a[i] = {y, x, 0};
    }
    for (int i = 1; i <= m; i++) vec[a[i].l].emplace_back(i), vec[a[i].r].emplace_back(-i);

    for (int i = 0; i < 26; i++) g[i][0] = 1;
    
    for (int i = 1; i <= n; i++)
    {
        for (auto x : vec[i])
        {
            if (x > 0) st[a[x].tp].emplace(a[x].l, x);
            else st[a[-x].tp].erase(make_pair(a[-x].l, -x));
        }
        for (int j = 0; j < 26; j++) f[j] = 0;
        int p0 = (st[0].size() ? st[0].begin() -> first : 0), p1 = (st[1].size() ? st[1].begin() -> first : 0);
        int pos = max(p0, p1);
        if (pos < i)
        {
            int sum = 0;
            for (int j = 0; j < 26; j++) f[j] = g[j][i - 1] - (pos ? g[j][pos - 1] : 0), add(sum, f[j]);
            for (int j = 0; j < 26; j++) f[j] = sbu(sum, f[j]);
        }
        if (p0 < p1)
        {
            int sum = 0;
            for (int j = 25; ~j; j--) add(f[j], sum), add(sum, g[j][p1 - 1] - (p0 ? g[j][p0 - 1] : 0));
        }
        else if (p1 < p0)
        {
            int sum = 0;
            for (int j = 0; j < 26; j++) add(f[j], sum), add(sum,  g[j][p0 - 1] - (p0 ? g[j][p1 - 1] : 0));
        }
        for (int j = 0; j < 26; j++) g[j][i] = adu(g[j][i - 1], f[j]);
    }
    int sum = 0;
    for (int j = 0; j < 26; j++) add(sum, f[j]);
    cout << (ll)sum * Qpow(25, mod - 2) % mod << '\n';
    return 0;
}