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Dr. Michael P Sack, D.C.

Dr. Michael P Sack is a Chiropractor provider (Chiropractor) practicing in Spearfish, SD, registered in the NPPES registry with NPI 1639100076 since 2006. The credential DC stands for Doctor of Chiropractic.

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NPI 1639100076
Entity type Individual (Type 1)
Name Dr. Michael P Sack
Credential D.C.
Sex Male
Practice address 144 N MAIN ST, Spearfish, SD, 57783
Phone 6056441111
Fax 6056441234
Enumeration date 2006-07-05
Last updated in NPPES 2014-08-25

Taxonomy & licenses

Taxonomy code Specialty Primary License State
111N00000X Chiropractor Primary 588 SD

DC — Doctor of Chiropractic: A licensed chiropractor focusing on musculoskeletal and nervous system disorders. About the DC credential

Copy-ready billing details
Provider: Michael Sack, D.C.
NPI: 1639100076
Taxonomy: 111N00000X (Chiropractor)
Address: 144 N MAIN ST, Spearfish, SD, 57783

Other providers at this practice address

NPI Name Type Specialty Location
1538340518 Sack Chiropractic PC Organization Chiropractor Spearfish, SD
1386091338 Acupuncture of the Black Hills, LLC Organization Acupuncturist Spearfish, SD
1104273150 Dylan Brandenburg Individual Acupuncturist Spearfish, SD

Verify this record

Cross-check NPI 1639100076 against the authoritative CMS record: view Dr. Michael P Sack on the official NPPES registry .

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. Read the full guide or validate an NPI number.

Frequently asked questions

How do I verify Michael Sack's NPI record?
Cross-check NPI 1639100076 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1639100076 active?
Yes — as of the latest NPPES snapshot, NPI 1639100076 is active (record last updated 2014-08-25).

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2014-08-25.