JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<form>
     <p><input type="text" id="cpf" name="cpf"/><span id="resposta"></span></p>
     <p><input id="cadastrar" name="cadastrar" type="submit" value="Cadastrar" disabled /></p>
   </form>

JavaScript

function CPF(){"user_strict";function r(r){for(var t=null,n=0;9>n;++n)t+=r.toString().charAt(n)*(10-n);var i=t%11;return i=2>i?0:11-i}function t(r){for(var t=null,n=0;10>n;++n)t+=r.toString().charAt(n)*(11-n);var i=t%11;return i=2>i?0:11-i}var n="CPF Inválido",i="CPF Válido";this.gera=function(){for(var n="",i=0;9>i;++i)n+=Math.floor(9*Math.random())+"";var o=r(n),a=n+"-"+o+t(n+""+o);return a},this.valida=function(o){for(var a=o.replace(/\D/g,""),u=a.substring(0,9),f=a.substring(9,11),v=0;10>v;v++)if(""+u+f==""+v+v+v+v+v+v+v+v+v+v+v)return n;var c=r(u),e=t(u+""+c);return f.toString()===c.toString()+e.toString()?i:n}}

    var CPF = new CPF();

    $(document).ready(function(){   
      $("#cpf").keyup(function(){
      var teste = CPF.valida($(this).val());
      $("#resposta").html(teste);
        if(teste == "CPF Válido"){ 
           $("#cadastrar").removeAttr("disabled");
        }else {    
           $("#cadastrar").attr("disabled",true);
        }
   });

    $("#cpf").blur(function(){
     var teste= CPF.valida($(this).val());
     $("#resposta").html(teste);
        if(teste == "CPF Válido"){ 
           $("#cadastrar").removeAttr("disabled");
        } else {
           $("#cadastrar").attr("disabled",true);
        } 
      });
    });