import java.util.Scanner;

public class Main{

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long n = sc.nextLong();
	    long nlen = String.valueOf(n).length(); 
	    for (long i = 1; i * i <= n; i++) {    
	        if (n % i == 0) {      
                if (String.valueOf(n/i).length() < nlen ){
                	nlen = String.valueOf(n/i).length();
	            }
	        }
	    }
	    System.out.println(nlen);
	    
	    
	}

}
/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