var atual = 600000.00;
//com R$
var f = atual.toLocaleString('pt-br',{style: 'currency', currency: 'BRL'}).replace(".", ",");
//sem R$
var f2 = atual.toLocaleString('pt-br', {minimumFractionDigits: 2}).replace(".", ",");
const atual = 600000.00;
const valorFormatado = Intl.NumberFormat('pt-br', {style: 'currency', currency: 'BRL'}).format(atual)