import java.util.*;

public class Main{

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int sqrtN=(int)Math.sqrt(N);
        int result=0;
        for(int i=1;i<sqrtN+1;i++){
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        }
        System.out.println(result);
        return;


    }
} import java.util.*; util.* java public class Main{

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int sqrtN=(int)Math.sqrt(N);
        int result=0;
        for(int i=1;i<sqrtN+1;i++){
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        }
        System.out.println(result);
        return;


    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int sqrtN=(int)Math.sqrt(N);
        int result=0;
        for(int i=1;i<sqrtN+1;i++){
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        }
        System.out.println(result);
        return;


    } main {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int sqrtN=(int)Math.sqrt(N);
        int result=0;
        for(int i=1;i<sqrtN+1;i++){
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        }
        System.out.println(result);
        return;


    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long N = sc.nextLong(); N sc.nextLong() sc.nextLong sc int sqrtN=(int)Math.sqrt(N); sqrtN (int)Math.sqrt(N) Math.sqrt Math N int result=0; result 0 for(int i=1;i<sqrtN+1;i++){
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        } int i=1; int i=1; i 1 i<sqrtN+1 i sqrtN+1 sqrtN 1 i++ i++ i {
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        } {
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        } if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            } N%i==0 N%i N i 0 {
                result=(int)Math.log10(N/i)+1;
            } result=(int)Math.log10(N/i)+1 result (int)Math.log10(N/i)+1 (int)Math.log10(N/i) Math.log10 Math N/i N i 1 System.out.println(result) System.out.println System.out System System.out result return; String[] args args public class Main{

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int sqrtN=(int)Math.sqrt(N);
        int result=0;
        for(int i=1;i<sqrtN+1;i++){
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        }
        System.out.println(result);
        return;


    }
} public class Main{

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int sqrtN=(int)Math.sqrt(N);
        int result=0;
        for(int i=1;i<sqrtN+1;i++){
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        }
        System.out.println(result);
        return;


    }
} Main
import java.util.*;

public class Main{

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        int sqrtN=(int)Math.sqrt(N);
        int result=0;
        for(int i=1;i<sqrtN+1;i++){
            if(N%i==0){
                result=(int)Math.log10(N/i)+1;
            }
        }
        System.out.println(result);
        return;


    }
}
