Michael Flessner, MD
NPI 1669401857 · Internal Medicine Physician · Frederick, MD
Michael Flessner, MD is a Internal Medicine Physician provider in Frederick, MD (NPI 1669401857).
Provider details
- NPI number
- 1669401857
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- D0035499 (MD)
Specialties & taxonomies
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
- 2006-07-01
- Last updated
- 2016-12-06
Frequently asked questions
- What is Michael Flessner's NPI number?
- Michael Flessner's National Provider Identifier (NPI) is 1669401857, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Michael Flessner's specialty?
- Michael Flessner is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Michael Flessner located?
- Michael Flessner's practice location on file with NPPES is 100 S Market St, Frederick, MD 21701-5527.
- What is Michael Flessner's phone number?
- The practice phone number listed in the NPPES registry for Michael Flessner is (301) 600-1506.
- Is Michael Flessner's NPI active?
- Yes — Michael Flessner's NPI (1669401857) is active in the NPPES registry as of the last update on 2016-12-06.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.