Mark Klein, M.D.
Mark Klein, M.D. is a Specialist in Washington, DC, registered under NPI 1194776419.
Getting there
The practice address on file is 2141 K ST NW STE 900, Washington, DC 20037. 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 |
|---|---|---|
| MD11986 | DC | Specialist primary |
This provider holds licence MD11986 issued in DC. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Diagnostic Radiology
- PAC ID
- 6901955574
Medicare enrolment is recorded as approved under the provider type Practitioner - Diagnostic Radiology. This means the provider is enrolled to bill Medicare, though it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Specialist covers
An individual educated and trained in an applied knowledge discipline used in the performance of work at a level requiring knowledge and skills beyond or apart from that provided by a general education or liberal arts degree. NUCC Health Care Provider Taxonomy, code 174400000X
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 | 1194776419 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | May 12, 2006 |
| Last updated | Jan 16, 2008 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
2141 K ST NW STE 900 Washington, DC 20037 (202) 223-9722 Fax (703) 280-5098 |
| Mailing address |
3015 WILLIAMS DR STE 200 Fairfax, VA 22031 |
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 | 1 | 9 | 4 | 7 | 7 | 6 | 4 | 1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 1 | 9 | 4 | 5 | 7 | 3 | 4 | 2 |
Sum = 61 · next multiple of 10 = 70 · check digit = 9 · actual last digit = 9
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.