Yes, but only for about an hour - given say an hour to get out of the airport, an hour and a half to get back in (if your boarding pass is ready, add 45 minutes if not), 45 minutes x 2 to get into town and get back. I wouldn't advise it.
@GrandGourmand Hi I take the opportunity to ask about transit time in IST with Turkish. Do u think 1h,35 could be enough as an international transit passenger? I mean, it is directly proposed by the airline itself on its website. There are different options, but the one I was looking at proposes this short stopover on the way to. Thanks!
Venu P, You can take a taxi from the airport to Yesilkoy and visit the marina area for about an hour (or to excellent Aquaflorya Mall) at Florya. Whether it is worth the evisa is something you will decide on. Your Schengen must still be valid on the day you want to enter Turkey. That will be the supporting document to your evisa. "www.evisa.gov.tr/en/".