Daniel Feirtag, M.D.
Daniel Feirtag, M.D. is a Geriatric Medicine (Internal Medicine) Physician in Silver Spring, MD, registered under NPI 1659401131.
Getting there
The practice address on file is 3110 GRACEFIELD RD, Silver Spring, MD 20904. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| D0023855 | MD | Geriatric Medicine (Internal Medicine)… primary |
This provider holds licence D0023855 issued in MD. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Geriatric Medicine covers
An internist who has special knowledge of the aging process and special skills in the diagnostic, therapeutic, preventive and rehabilitative aspects of illness in the elderly. This specialist cares for geriatric patients in the patient's home, the office, long-term care settings such as nursing homes and the hospital. NUCC Health Care Provider Taxonomy, code 207RG0300X
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1659401131 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Mar 6, 2007 |
| Last updated | Jul 16, 2009 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
3110 GRACEFIELD RD Silver Spring, MD 20904 (301) 572-8340 Fax (301) 572-8403 |
| Mailing address |
PO BOX 17296 Baltimore, MD 21297 |
| Other identifiers |
0054
· Other 0943ER-311120-02 · Other 311120-02 · Other P17416 · Other 04-21635 · Other 312031700 · Medicaid (MD) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 6 | 5 | 9 | 4 | 0 | 1 | 1 | 3 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 6 | 1 | 9 | 8 | 0 | 2 | 1 | 6 |
Sum = 59 · next multiple of 10 = 60 · check digit = 1 · actual last digit = 1
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.