If we’re walking towards each other going opposite directions on the sidewalk or he’s sitting next to my path, he can say “good evening” (I live in a small city in Germany where this is common), ask me for something (I’m picturing panhandlers or smokers asking for a light), or tell me my shoelaces are untied, but I will definitely get a jolt of fear if a man follows or obviously goes out of his way to approach me at night when I’m alone.
If it’s multiple men, it can be more or less scary, depending on whether they seem sober. More men obviously have an even better chance of overpowering me, but I don’t actually distrust men as a whole, so the more there are in the group, the less likely it is that they’re all down to harm a woman. Of course, once we get up to 8+ men, peer pressure might make it difficult for some to speak up.
If a handsome, seemingly rich man approached me alone at night (for non shoelace/lighter reasons), I would be more concerned, like the other commenters. A) that feels like bait; B) I’m married and uninterested anyway, so it’s not effective bait; C) he’s still capable of overpowering me; and D) he’s less likely to be accepting of a no than a panhandler
If that man was driving, there are no circumstances where it wouldn’t scare me if he approached. Sometimes people are lost and they’ve got no phone battery or atlas, and I can imagine an innocent situation in which someone in a car might seek me out alone at night to ask for directions.
I might even give them, if I could ensure that there was a physical barrier between me and the car so I couldn’t be snatched. It would still definitely give me a shock though.