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Yes, it is possible to deeply freeze an object in JavaScript using the Object.freeze() method recursively on all its nested properties. Here is an example code snippet to achieve this:

function deepFreeze(obj) {
  Object.freeze(obj);
  Object.getOwnPropertyNames(obj).forEach(prop => {
    if (obj.hasOwnProperty(prop) && obj[prop] !== null && (typeof obj[prop] === "object" || typeof obj[prop] === "function") && !Object.isFrozen(obj[prop])) {
      deepFreeze(obj[prop]);
    }
  });
  return obj;
}

const obj = {
  prop1: {
    nestedProp: {
      array: [1, 2, 3]
    }
  },
  prop2: "hello"
};

deepFreeze(obj);

// Trying to modify any properties of the object would fail silently in strict mode
obj.prop2 = "world"; // This would have no effect
obj.prop1.nestedProp.array.push(4); // This would also have no effect