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Gerontology Network

Geriatric Psychiatry Physician in Grand Rapids, MI · enumerated 2007 · authorized official Thomas Hartwig, President Ceo.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1649306879

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Registry record

Entity type Organization (Type 2)
Legal business name Gerontology Network
Practice address 516 Cherry St Se, Grand Rapids, MI, 49503
Phone (616) 456-6135
Enumeration date Feb 23, 2007
Last updated in NPPES May 2, 2008

Taxonomy & classification

101YM0800X Mental Health Counselor Behavioral Health & Social Service Providers Secondary
1041C0700X Clinical Social Worker Behavioral Health & Social Service Providers Secondary
2084P0800X Psychiatry Physician Allopathic & Osteopathic Physicians Secondary
2084P0805X Geriatric Psychiatry Physician Allopathic & Osteopathic Physicians Primary
251B00000X Case Management Agency Agencies Secondary

Authorized official

Name Thomas Hartwig
Title President Ceo
Phone (616) 456-6135

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty.

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Frequently asked questions

Who is the authorized official for Gerontology Network?
NPPES lists Thomas Hartwig (President Ceo) as the authorized official for this organization.
What is the NPI number for Gerontology Network?
The NPI for Gerontology Network is 1649306879, a Type 2 (organization) record in the CMS NPPES registry.

Providers at this address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-05-02.