Zachary Williamson, M.D.
Zachary Williamson, M.D. is a Public Health & General Preventive Medicine Physician in Princeton, NJ, registered under NPI 1346668928. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 508 CARNEGIE CTR, Princeton, NJ 08540. 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 |
|---|---|---|
| MD463202 | PA | Public Health & General Preventive… primary |
This provider holds licence MD463202 issued in PA. 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
- Order And Referring Only - Preventive Medicine
- PAC ID
- 0840588216
Medicare enrolment is recorded as approved under the provider type Order And Referring Only - Preventive Medicine. 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 Public Health & General Preventive Medicine covers
Public health and general preventive medicine focuses on promoting health, preventing disease, and managing the health of communities and defined populations. These practitioners combine population-based public health skills with knowledge of primary, secondary, and tertiary prevention-oriented clinical practice in a wide variety of settings. NUCC Health Care Provider Taxonomy, code 2083P0901X
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 | 1346668928 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Apr 1, 2014 |
| Last updated | Jan 23, 2020 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | M.D. |
| Practice address |
508 CARNEGIE CTR Princeton, NJ 08540 (609) 524-6788 |
| Mailing address |
111 W JACKSON BLVD STE 1400 Chicago, IL 60604 |
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 | 3 | 4 | 6 | 6 | 6 | 8 | 9 | 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 3 | 8 | 6 | 3 | 6 | 7 | 9 | 4 |
Sum = 72 · next multiple of 10 = 80 · check digit = 8 · actual last digit = 8
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.