#include <bits/stdc++.h>
int main(int argc, const char* argv[]) {
  long long int n;
  (scanf("%lld", &n));
  ;
  long long int asallar[] = {
      2,   3,   5,   7,   11,  13,  17,  19,  23,  29,  31,  37,  41,  43,  47,
      53,  59,  61,  67,  71,  73,  79,  83,  89,  97,  101, 103, 107, 109, 113,
      127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197,
      199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281,
      283, 293, 307, 311, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379,
      383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463,
      467, 479, 487, 491, 499, 503, 509, 521, 523, 541, 547, 557, 563, 569, 571,
      577, 587, 593, 599, 601, 607, 613, 617, 619, 631, 641, 643, 647, 653, 659,
      661, 673, 677, 683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761,
      769, 773, 787, 797, 809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863,
      877, 881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977,
      983, 991, 997, 1001};
  long long int x = 0;
  long long int prints[5000];
  long long int memC = 0;
  while (asallar[x] <= n) {
    long long int t = 1;
    long long int w = asallar[x];
    while (t * w <= n) {
      prints[memC] = t * w;
      memC++;
      t *= w;
    }
    x++;
  }
  printf("%lld", memC);
  puts("");
  for (long long int i = 0; i < (memC); i++) {
    printf("%lld ", prints[i]);
  }
  return 0;
}
