Twenty-five is a magic number at Christian Book Distributors in Peabody. Employees who have put in a quarter-century at the 33-year-old Christian catalog company get 25 extra vacation days, two plane tickets to any destination in the United States or the Caribbean, and a $2,500 bonus. Vice president Rick Brown, 52, used his time off to take his family to see the redwoods in California, Yellowstone National Park, and Mount Rushmore, and hang out with his daughter before she left for college. The only drawback: the 2,000 e-mails that piled up in his inbox while he was away. So far, 14 of the company’s 500 employees have hit the 25-year mark; in 2016, nine people will reach the milestone, but president and owner Ray Hendrickson isn’t worried about busting the budget. “I couldn’t be more thrilled,” said Hendrickson, who is already trying to figure out what to do when the first employees hit 35 years.