genial, friendly, affable, cordial, congenial, amiable, warm, easy-going, approachable, sympathetic, well disposed, good-natured, cheerful, cheery, neighbourly, hospitable, companionable, comradely, bluff, easy to get along with
sociable, convivial, outgoing, extrovert, extroverted, gregarious, company-loving, hail-fellow-well-met
informal chummy, pally
British informal matey
North American informal buddy-buddy, clubby, regular