MICHAEL DAVID MARCHISELLI
NPI 1255845590
Peer Specialist in San Francisco, CA

NPI Status: Active since November 22, 2017

Contact Information

1990 41ST AVE
SAN FRANCISCO, CA
ZIP 94116
Phone: (415) 753-7400

NPI Profile Information
Primary Taxonomy
NPI Validation
Other Providers Same Location
Frequently Asked Questions

Individual
Male
Peer Specialist

About MICHAEL MARCHISELLI

This page provides the complete NPI Profile along with additional information for Michael Marchiselli, a provider established in San Francisco, California with a medical specialization in Peer Specialist. The healthcare provider is registered in the NPI registry with number 1255845590 assigned on November 2017. The practitioner's primary taxonomy code is 175T00000X. The provider is registered as an individual and his NPI record was last updated one year ago.

NPI: 1255845590
Provider Name: MICHAEL DAVID MARCHISELLI
Gender: Male
Entity Type: Individual
Location Address: 1990 41ST AVE SAN FRANCISCO, CA 94116
Location Phone: (415) 753-7400
Mailing Address: 1761 PAGE ST SAN FRANCISCO, CA 94117
Mailing Phone: (415) 684-4629
Is Sole Proprietor?: No
Enumeration Date: 11-22-2017
Last Update Date: 11-18-2025
Code Navigator

Location Map

Specialty - Primary Taxonomy

The NPI enumerator requires providers to submit at least one taxonomy code. A taxonomy code is a unique 10-character code that describes the healthcare provider type, classification, and the area of specialization. There could be only one primary taxonomy code per NPI record. For individual NPIs the license data is associated to the taxonomy code.

Classification: Peer Specialist
Taxonomy Code: 175T00000X
Type: Other Service Providers
License State: CA
Taxonomy Description: Individuals certified to perform peer support services through a training process defined by a government agency, such as the Department of Veterans Affairs or a state mental health department/certification/licensing authority.

NPI NPI Number Validation

How NPI Validation Works

The NPI validation process uses the ISO-standard Luhn algorithm, a mathematical "handshake", to ensure that a provider's 10-digit ID is authentic and free of common typing errors.

To verify the NPI 1255845590, we treat the final digit (0) as the Check Digit—the target answer we need to reach. The process begins by taking the first nine digits and adding a constant value of 24, which accounts for the "80840" prefix required for all U.S. health identifiers. We then double every other digit starting from the right and sum the individual digits of those results together. For this specific NPI, that total comes to 60. The final step is to find the difference between that total and the next multiple of ten (60 - 60 = 0).

Digit-by-digit view

Use the first nine digits for the calculation. Starting from the right, double every other digit. The last digit is the check digit and is not part of the calculation.

Pos 1

Doubled → 2

Pos 2

Unchanged

Pos 3

Doubled → 10 → 1 + 0

Pos 4

Unchanged

Pos 5

Doubled → 16 → 1 + 6

Pos 6

Unchanged

Pos 7

Doubled → 10 → 1 + 0

Pos 8

Unchanged

Pos 9

Doubled → 18 → 1 + 8

Check

Target digit

Regular digit Doubled digit Check digit

Step 1: Double every other digit from the right

Starting with the rightmost digit of the first nine digits, double every other value. If doubling creates a two-digit number, add those digits together.

1 → 2 5 → 10 → 1 8 → 16 → 7 5 → 10 → 1 9 → 18 → 9

Step 2: Add all digits plus the NPI constant

Add the transformed values, the unchanged digits, and the constant 24.

2 + 2 + 1 + 0 + 5 + 1 + 6 + 4 + 1 + 0 + 5 + 1 + 8 + 24 = 60

Step 3: Find the amount needed to reach the next multiple of 10

The next multiple of ten after 60 is 60. The difference is the calculated check digit.

60 - 60 = 0

This NPI is valid

The calculated check digit is 0, which matches the last digit of 1255845590.