import java.util.Scanner;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int count=0;
        String B;
        for(int i=1; i<=Math.sqrt(N); i++){
            if(N%i==0){
                B = String.valueOf(N/i);
                count = B.length();
            }
        }
          System.out.println(count);
        }
    }

/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