#include <bits/stdc++.h>
#pragma GCC optimize("O2,unroll-loops")
using namespace std;
const int inf = 1000000010;
const long long INF = 10000000000000010LL;
const int mod = 1000000007;
const int MAXN = 1000010, LOG = 20;
long long n, m, k, u, v, x, y, t, a, b, ans;
int sieve[MAXN];
long long A[MAXN], B[MAXN];
vector<pair<long long, long long> > vec[MAXN];
void add(long long x, long long l, long long r) {
  x--;
  for (; x > 1; x /= sieve[x]) {
    long long p = sieve[x];
    if (k <= l)
      A[p] += r - l;
    else if (r <= k)
      vec[p].push_back({l, r});
    else {
      vec[p].push_back({l, k});
      A[p] += r - k;
    }
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  for (int i = 2; i < MAXN; i++)
    if (!sieve[i])
      for (int j = i; j < MAXN; j += i) sieve[j] = i;
  cin >> n;
  while (n--) cin >> x >> y, B[x] = y;
  cin >> k;
  for (int i = 1; i < MAXN; i++)
    if (B[i]) {
      if (B[i] <= k)
        vec[i].push_back({0, B[i]});
      else {
        A[i] += B[i] - k;
        vec[i].push_back({0, k});
      }
    }
  for (int i = MAXN - 1; i > 1; i--)
    if (vec[i].size()) {
      sort(vec[i].begin(), vec[i].end());
      for (int j = 1; j < vec[i].size(); j++)
        if (vec[i][j].first < vec[i][j - 1].second) {
          long long x = vec[i][j - 1].second - vec[i][j].first;
          vec[i][j - 1].second = vec[i][j].first;
          vec[i][j].second += x;
        }
      for (pair<long long, long long> p : vec[i]) {
        long long l = p.first, r = p.second;
        if (r <= k)
          add(i, l + 1, r + 1);
        else if (k <= l)
          A[i] += r - l;
        else {
          add(i, l + 1, k + 1);
          A[i] += r - k;
        }
      }
    }
  for (int i = 2; i < MAXN; i++) ans += (A[i] > 0);
  cout << ans << "\n";
  for (int i = 2; i < MAXN; i++)
    if (A[i] > 0) cout << i << " " << A[i] << "\n";
  return 0;
}
