import java.util.*;
class Main{
    public static void main(String[]args){
        Scanner cin=new Scanner(System.in);
        long input;
        long larger;
        int min=11;
        input=cin.nextLong();
        for(long i=1;i*i<=input;i++){
            if(input%i==0){
                larger=(long)input/i;
                if(min>String.valueOf(larger).length()){
                    min = String.valueOf(larger).length();
                }
            }
        }
        System.out.println(min);
    }
}

/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