This drastically depends on ones definition of a "friend." I have male friends who probably wouldn't mind getting with me, if they were single, I was single and both horny. Same with me, I have guy friends who are very attractive they're also married, I'm about to be and we're all just a merry bunch of friends. I've hung out with them a few times one on one alone, but it's quite rare. I think so what if one party thinks the other is good looking I think most of my friends are both male and female- so? Does that have an impact on friendship? Not really... My partner trusts me, trusts them so what's the big deal?
Basically my definition of a friend is simply: you get along, laugh, trust each other and have fun together. That is all. So yes, males and females can be that. Even IF they wanted me, they know it ain't gonna happen they still enjoy laughing, talking, and having fun which is my definition.
Now if you asked me can an attractive man and an attractive woman who are single be just friends and by friends I mean hanging out one on one regularly, doing couple-ish things together, and chatting on the phone for hours at a time... be just friends I would change my answer and it would simply and obviously no.