Excluding recent development on javascript such as es6 , yes all function are objects ,because of lose typing in JS. For example, in the following code, JavaScript engine treats everything (not everything, but for emphasis) as an object ,be it string ,number ,boolean and functions .
Hope u have gained a tiny window into how JS object works
var car = {
name: 'string',
carNumber: 12 + 34,
carPerformance: function () {
return someThing;
},
car: 3 + 2,
isCarOk: true,
};
//to call it
car[name];
car.carPerformance