If she is interested in reading on her own, then I agree with Stephanie's suggestion: Teach Your Child To Read in 100 Easy Lessons. I did it with our 2 kids. It was fantastic.
If she is NOT interested in reading (asking you how, "guessing" what words are in books and on signs when you are out in public, pretending to read things you know she can't, getting excited when she does recognize words on signs, etc) then don't push it.
You can work on basic math skills (since she knows her numbers) like adding things. One block plus one block is 2 blocks, etc.
But again, it ALL needs to be fun. Not drills or flashcard type stuff.
Talk to her about HOW things happen/work too. Not just facts (name of colors, letters, etc), but the "how". The plants need sunshine to give them energy for growing. Then they make seeds that fall to the ground (or get carried away by birds who have eaten berries and then poop, distributing the seeds elsewhere) and germinate. Starting the cycle all over again.
Explain how the car goes. That you have to put fuel (gas) into the tank for the car to be able to go. That pressing the gas pedal makes the fuel go into the engine where it burns producing the energy that makes the car go.
Use simple terminology and explanations that she can understand. Who cares if you don't know all the science behind it all... it will get her mind thinking about how and why things happen! She will let you know if you give her more information than she can process (she'll tune you out and change the subject or she'll ask more questions, sometimes more than you can answer properly!).
You can explain things like breathing. Take her to Walmart/Petsmart to look at the fish and explain how we breathe, then how fish breathe. Your body needs oxygen (part of the air) to function, and when you breathe in, your lungs grab those oxygen parts and send them to all the parts of your body that need it. In fish, they don't have lungs, they have gills. And their gills do for them, what our lungs do for us. :)
These, obviously, are just a few examples... but you can explain just about ANYTHING that catches her attention.
Everyday doesn't have to be a "lesson"... but there are mini-lessons built in to everyday stuff all around you.
I would definitely encourage her to spend time coloring, playing with play-doh and playing with small items (like stringing beads, etc). These things build the muscles and fine motor skills she will need when learning to write later on, and learning to tie shoes, etc.