import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    long N = in.nextLong();

    int ans = digit(N);
    for (long i = 1; i <= Math.sqrt(N); i++) {
      if (N % i == 0) {
        ans = Math.min(ans, digit(N / i));
      }
    }

    System.out.println(ans);
  }

  public static int digit(long l) {
    return String.format("%d", l).length();
  }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz