Curable composition, and cured product

A curable composition comprising:

• an oxyalkylene polymer A having a reactive silicon group represented by the following formula (1) and having 6 or more terminal groups,
• wherein the terminal group contains at least one selected from the group consisting of a reactive silicon group represented by the formula (1), an active hydrogen-containing group, and an unsaturated group,
• the oxyalkylene polymer A comprises 0.3 or more of the reactive silicon group per terminal group, and
• a number average molecular weight of the oxyalkylene polymer A is more than 25,000 and not more than 100,000,
• —SiRa(X)3-a (1)
• wherein, in formula, R is a monovalent organic group having 1 to 20 carbon atoms and represents an organic group other than a hydrolyzable group, and X represents a hydroxyl group, a halogen atom, or a hydrolyzable group, a is an integer of 0 to 2, when a is 2, R groups may be the same as or different from each other, and when a is 0 or 1, X groups may be the same as or different from each other.