Individual provider

Mohammed Siddiqui, MD

Geriatric Psychiatry Physician Medicare enrolled

Mohammed Siddiqui, MD is a Geriatric Psychiatry Physician in Lombard, IL, registered under NPI 1639456122. 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 477 E BUTTERFIELD RD STE 102, Lombard, IL 60148. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

477 E BUTTERFIELD RD STE 102, Lombard, IL 60148 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
036-131386 IL Geriatric Psychiatry Physician primary

This provider holds licence 036-131386 issued in IL. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Psychiatry
PAC ID
8729224720
Enrollment ID
I20130417000630

Medicare enrolment is recorded as approved under the provider type Practitioner - Psychiatry. 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 Geriatric Psychiatry covers

Geriatric Psychiatry is a subspecialty with psychiatric expertise in prevention, evaluation, diagnosis and treatment of mental and emotional disorders in the elderly, and improvement of psychiatric care for healthy and ill elderly patients. NUCC Health Care Provider Taxonomy, code 2084P0805X
Allopathic & Osteopathic Physicians Psychiatry & Neurology Geriatric Psychiatry

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.

NPI1639456122 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateNov 10, 2011
Last updatedNov 20, 2025
StatusActive
Sole proprietorYes
GenderMale
CredentialMD
Practice address 477 E BUTTERFIELD RD STE 102
Lombard, IL 60148
(630) 528-3835
Fax (630) 528-3837
Other identifiers 036131386 · Medicaid (IL)
This record was updated on Nov 20, 2025, which is recent enough that the contact details are likely still accurate.

Number check

1639456122 passes the NPI check digit test The final digit 2 matches the value computed from the first nine digits, so this is a well-formed NPI.
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 3 9 4 5 6 1 2
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 6 6 9 8 5 3 1 4

Sum = 68 · next multiple of 10 = 70 · check digit = 2 · actual last digit = 2

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.

Common questions

What is NPI number 1639456122?
NPI 1639456122 is the National Provider Identifier assigned to Mohammed Siddiqui, MD in Lombard, IL. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Geriatric Psychiatry cover?
Geriatric Psychiatry is a subspecialty with psychiatric expertise in prevention, evaluation, diagnosis and treatment of mental and emotional disorders in the elderly, and improvement of psychiatric care for healthy and ill elderly patients.
How do I contact Mohammed Siddiqui, MD?
The phone number on file with NPPES is (630) 528-3835, last updated Nov 20, 2025. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Mohammed Siddiqui, MD accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1639456122 a valid number?
Yes. 1639456122 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.