Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Roy B Blumenstrauch, M.D.

Specialist in Torrance, CA · enumerated 2005.

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

National Provider Identifier

1639175409

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Registry record

Entity type Individual (Type 1)

Name Dr. Roy B Blumenstrauch

Credential M.D.

Sex Male

Practice address 4201 Torrance Blvd, Ste 640, Torrance, CA, 90503

Phone (310) 543-4444

Fax (310) 543-4446

Enumeration date Jun 24, 2005

Last updated in NPPES Nov 27, 2007

Taxonomy & licenses

174400000X Specialist Other Service Providers · License G54548 (CA) 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.

Read the full guide → Validate an NPI →

Frequently asked questions

Is NPI 1639175409 active?

Yes, as of the latest NPPES snapshot, NPI 1639175409 is active (record last updated 2007-11-27).

How do I verify Roy Blumenstrauch's NPI record?

Cross-check NPI 1639175409 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 2007-11-27.