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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Joseph Alexander Mack, MD

Internal Medicine Physician in Marietta, OH · enumerated 2006.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1669581880

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Registry record

Entity type Individual (Type 1)
Name Joseph Alexander Mack
Credential MD
Sex Male
Practice address Marietta, OH, 45750
Phone (740) 376-1994
Fax (740) 374-7701
Enumeration date Aug 30, 2006
Last updated in NPPES Jul 22, 2021

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

208M00000X Hospitalist Physician Allopathic & Osteopathic Physicians · License 35075546 (OH) Secondary
207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 35.075546 (OH) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

How do I verify Joseph Mack's NPI record?
Cross-check NPI 1669581880 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1669581880 active?
Yes, as of the latest NPPES snapshot, NPI 1669581880 is active (record last updated 2021-07-22).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2021-07-22.