Do you think a 17 years old age gap is a lot?

(my English is not good) I met this guy online he's amazing, I like his personality and I think he's cool, (we live in different countries), we've known each other for 3 months now he's 40, I'm 23 he's also serious about this connection and is asking me for marriage, I want to ask if the age gap is too much because I'm worried that it's gonna cause issues in our relationship in the future. Please be honest and give me ur opinions.

Do you think a 17 years old age gap is a lot?
Post Opinion