A simple knockout extender which coerces values to integers.
npm install knockout-integer
Then add knockout-integer.js to your project.
require the script in your bundle. Then:
var myNumber = ko.observable().extend({integer: 0 /* optional default value if it cannot be coerced to integer */});
myNumber("17000");
console.log(myNumber()); //17000
console.log(myNumber.formatted()); //17,000