look at it logically - would you approach a man almost double your age and give him your number? You may think you are very mature but in all honesty Ann321 you ain't! Older men come on to younger, attractive females all the time and it's not always for their intellect !. You have obviously put out certain vibes to this man which on your part may well have been just a bit of friendly banter (always a tricky area - what one persons looks at as a bit of fun, others look on as serious) He's obviously not seen it this way and wants to take it further. Do you want this?
It may turn out to be the romance of the century but I doubt it -the fact that you think he is a little immature is not a good sign to me. Take care.