I want to update the description of the app plus the screenshots on play store but the app remains the same viz same version number(I don't want to publish new app since nothing in app is changed)
Is that possible or will google ask for app to be updated as well.
You can update the description and can change screenshot also and your app will remain same only the description and screen will be updated within two hours, and you don't need to update apk.
google will never ask to update the apk file when you change description or distribution. below is the screen shot where yoiu have to edit description and change screen shot.