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Dr. Michael T Stack, MD PHD

Rheumatology Physician in Indianapolis, IN · enumerated 2005 · practices at Diagnostic Rheumatology and Research, PC.

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

National Provider Identifier

1770585945

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Registry record

Entity type Individual (Type 1)
Name Dr. Michael T Stack
Credential MD PHD
Sex Male
Practice address 6447 S East St Ste A, Indianapolis, IN, 46227
Phone (317) 859-6364
Fax (317) 859-7537
Enumeration date Jun 1, 2005
Last updated in NPPES Jan 6, 2022

Taxonomy & licenses

1744R1102X Research Study Specialist Other Service Providers · License 01026374 (IN) Secondary
207RR0500X Rheumatology Physician Allopathic & Osteopathic Physicians · License 01026374 (IN) Secondary
207RR0500X Rheumatology Physician Allopathic & Osteopathic Physicians · License 71508 (WI) Primary

Other identifiers

Identifier Type State Issuer
100133510B Medicaid IN -
1265457774 Other - OFFICE/GROUP NPI
100083069 Medicaid WI -
000000318888 Other IN BLUE CROSS BLUE SHIELD

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

Where does Michael Stack practice?
The practice location on file with NPPES is in Indianapolis, IN. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Michael Stack?
The National Provider Identifier (NPI) for Michael Stack is 1770585945, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2022-01-06.