// For integers use

function numberWithSpaces(x) {

return x.toString().replace(/\B(?=(\d{3})+(?!\d))/g, " ");

}

// For floating point numbers you can use

function numberWithSpaces(x) {

var parts = x.toString().split(".");

parts[0] = parts[0].replace(/\B(?=(\d{3})+(?!\d))/g, " ");

return parts.join(".");

}