Asia-Pacific Economic Cooperation, or APEC, is the premier forum for facilitating economic growth, cooperation, trade and investment in the Asia-Pacific region.
Provider Transaction Access Number (PTAN) A PTAN is a Medicare-only number issued to providers by MACs upon enrollment to Medicare. When a MAC approves enrollment and issues an approval letter, the letter will contain the PTAN assigned to the provider.
According to the article, your NPI is the ten-digit number that you enter on your claims to identify yourself as an entity eligible to bill Medicare for services performed. The PTAN, however, is a number that authenticates you when you contact Medicare contractors.