When resigning from employment a minimum of a two week notice is the standard unless there are extenuating circumstances.
It's common courtesy to give 2-weeks’ notice. Most employers understand that and are respectful of this.
Talk with your manager when you resign, offer to train the next person or if that isn’t possible you could create a manual of your position that the next person could use.
Remember you will always need a reference from that company (even 3 or 4 years from now) so leave under good terms no matter what.
I suggest remaining professional and do everything you can to leave on a high note and don't burn any bridges. How you leave will be remembered, I assure you of that.