Marissa Niemeyer, MSN, AGPCNP-C
Marissa Niemeyer, MSN, AGPCNP-C is a Gerontology Nurse Practitioner in Grand Rapids, MI, registered under NPI 1003485194.
Getting there
Here is what surrounds this office in Grand Rapids, based on OpenStreetMap data collected Sep 9, 2026. Parking is available about 501 ft away. The nearest transit stop is 724 ft away, served by Medical Mile Station (WB). If you arrive early, there is a coffee shop 0.43 mi away.
Getting here and what is nearby
Parking Ramp 7 356 ft ~2 min
Parking Ramp 8 453 ft ~2 min
Parking 501 ft ~2 min
Transit GRCC/Spectrum 718 ft ~3 min
Transit Medical Mile Station (EB) 723 ft ~3 min
Transit Medical Mile Station (WB) 724 ft ~3 min
Coffee Rowster Coffee 752 ft ~3 min
Restaurant Qdoba 980 ft ~4 min
25 Michigan Street Northeast, Grand Rapids 49503
Mo-Fr 10:30-23:00; Sa-Su 10:30-21:00
Restaurant Zoup! 1,004 ft ~4 min
25 Michigan Street Northeast, Grand Rapids
Restaurant McDonald's 0.26 mi ~6 min
417 Michigan Avenue, Grand Rapids 49503-3316
05:00-23:00
Coffee Bagel Beanery 0.34 mi ~7 min
Hotel Hyatt Place Grand Rapids/Downtown 0.38 mi ~8 min
Gas station Circle K 0.39 mi ~8 min
Convenience Circle K 0.40 mi ~8 min
514 Michigan Street Northeast, Grand Rapids 49503
Hotel Homewood Suites by Hilton Grand Rapids Downtown 0.40 mi ~8 min
161 Ottawa Avenue Northwest, Grand Rapids
Coffee Sweetwaters Coffee & Tea Monroe North 0.43 mi ~9 min
601 Bond Avenue Northwest, Grand Rapids
Hotel Hampton Inn & Suites Grand Rapids Downtown 0.45 mi ~9 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 4704330088 | MI | Gerontology Nurse Practitioner primary |
This provider holds licence 4704330088 issued in MI. 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 - Nurse Practitioner
- PAC ID
- 6901208040
- Enrollment ID
- I20221029000138
Medicare enrolment is recorded as approved under the provider type Practitioner - Nurse Practitioner. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Gerontology covers
Definition to come... NUCC Health Care Provider Taxonomy, code 363LG0600X
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 | 1003485194 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jun 22, 2021 |
| Last updated | Jan 31, 2025 |
| Status | Active |
| Sole proprietor | No |
| Gender | Female |
| Credential | MSN, AGPCNP-C |
| Practice address |
145 MICHIGAN ST NE STE 3410 Grand Rapids, MI 49503 (616) 391-9945 |
| Mailing address |
100 MICHIGAN ST NE # MC845 Grand Rapids, MI 49503 |
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 | 0 | 0 | 3 | 4 | 8 | 5 | 1 | 9 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 8 | 8 | 1 | 1 | 9 |
Sum = 56 · next multiple of 10 = 60 · check digit = 4 · actual last digit = 4
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.