import java.util.*;

public class Main{
  public static void main(String[]args){
    Scanner sc = new Scanner(System.in);
    long N = sc.nextLong();
    int A = 0, B = 0;
    for(int i = (int)Math.sqrt(N); i >= 1 ; i--){
      if(N%i == 0){
        A = i;
        B = (int)(N/i);
        break;
      }
    }
    System.out.println(calc(A,B));
  }
  public static int calc(int A, int B){
    int C = A > B ? A : B;
    int ans = 0;
    while(C > 0){
      C /= 10;
      ans++;
    }
    return ans;
  }
}
/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