Ralph Hanahan, M.D.
NPI 1801986641 · Therapeutic Radiology Physician · Santa Rosa, CA
Ralph Hanahan, M.D. is a Therapeutic Radiology Physician provider in Santa Rosa, CA (NPI 1801986641).
Provider details
- NPI number
- 1801986641
- Entity type
- Individual
- Primary specialty
- Therapeutic Radiology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- C30500 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-10-13
- Last updated
- 2025-09-11
Frequently asked questions
- What is Ralph Hanahan's NPI number?
- Ralph Hanahan's National Provider Identifier (NPI) is 1801986641, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Ralph Hanahan's specialty?
- Ralph Hanahan is listed in the NPPES registry with a primary specialty of Therapeutic Radiology Physician (Allopathic & Osteopathic Physicians).
- Where is Ralph Hanahan located?
- Ralph Hanahan's practice location on file with NPPES is 3555 Round Barn Cir, Santa Rosa, CA 95403-1757.
- What is Ralph Hanahan's phone number?
- The practice phone number listed in the NPPES registry for Ralph Hanahan is (707) 522-6875.
- Is Ralph Hanahan's NPI active?
- Yes — Ralph Hanahan's NPI (1801986641) is active in the NPPES registry as of the last update on 2025-09-11.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.