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William Benjamin Birnbaum, MD

Diagnostic Radiology Physician in Anaheim, CA · enumerated 2006.

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

National Provider Identifier

1225105745

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Registry record

Entity type Individual (Type 1)
Name William Benjamin Birnbaum
Credential MD
Sex Male
Practice address 1111 West La Palma Ave, Anaheim, CA, 92801
Phone (714) 999-6080
Fax (714) 999-3924
Enumeration date Nov 29, 2006
Last updated in NPPES Mar 7, 2023

Taxonomy & licenses

2085R0202X Diagnostic Radiology Physician Allopathic & Osteopathic Physicians · License G19532 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
RHL115594 Other CA DEPT OF HEALTH SERVICES
00G195320 Medicaid CA -

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

Is NPI 1225105745 active?
Yes, as of the latest NPPES snapshot, NPI 1225105745 is active (record last updated 2023-03-07).
How do I verify William Birnbaum's NPI record?
Cross-check NPI 1225105745 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-03-07.