Exhibit 4.1


 


NUMBER UNITS

U-[●]


 


SEE REVERSE FOR CERTAIN DEFINITIONS


 


CUSIP 74168P206


 


PRIME NUMBER ACQUISITION I CORP.


 


UNITS CONSISTING OF ONE SHARE OF CLASS A COMMON STOCK AND ONE-HALF
OF ONE REDEEMABLE WARRANT TO PURCHASE ONE

SHARE OF CLASS A COMMON STOCK AND ONE RIGHT TO RECEIVE ONE-EIGHTH OF ONE SHARE OF CLASS A COMMON
STOCK


 


THIS CERTIFIES THAT is the owner of Units.


 


Each Unit (“Unit”)
consists of one (1) share of Class A common stock, par value $0.0001 per share (“Common Stock”), of
Prime Number Acquisition I Corp., a Delaware corporation (the “Company”), one-half of one redeemable warrant
(each, a “Warrant”), and one right (each a “Right”). Each Warrant entitles the holder
to purchase one (1) share (subject to adjustment) of Common Stock for $11.50 per share (subject to adjustment). Each Warrant will
become exercisable on the later of (i) the Company’s completion of a merger, capital stock exchange, asset acquisition, stock
purchase, reorganization or other similar business combination with one or more businesses (each a “Business Combination”),
or (ii) twelve (12) months from the closing of the Company’s initial public offering, and will expire unless exercised before
5:00 p.m., New York City Time, on the date that is five (5) years after the date on which the Company completes its initial Business
Combination, or earlier upon redemption or liquidation (the “Expiration Date”). The Common Stock, Warrants,
and Rights comprising the Units represented by this certificate are not transferable separately prior to [●], 2022, unless Prime
Number Capital LLC elects to allow earlier separate trading, subject to the Company’s filing of a Current Report on Form 8-K
with the Securities and Exchange Commission containing an audited balance sheet reflecting the Company’s receipt of the gross proceeds
of the offering and issuing a press release announcing when separate trading will begin. The terms of the Warrants are governed by a Warrant
Agreement, dated as of [●], 2022, between the Company and VStock Transfer, LLC, as Warrant Agent, and are subject to the terms and
provisions contained therein, all of which terms and provisions the holder of this certificate consents to by acceptance hereof. Copies
of the Warrant Agreement are on file at the office of the Warrant Agent at 18 Lafayette Place, Woodmere, New York 11598, and are available
to any Warrant holder on written request and without cost.


 


This certificate is not valid
unless countersigned by the Transfer Agent and Registrar of the Company.


 


This certificate shall be
governed by and construed in accordance with the internal laws of the State of New York.


 


Witness the facsimile signature of its duly authorized
officers.


 


	 	 	 
	Chief Executive Officer 
	 	Chief Financial Officer





 






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PRIME NUMBER ACQUISITION I CORP.


 


The Company will furnish without
charge to each unitholder who so requests, a statement of the powers, designations, preferences and relative, participating, optional
or other special rights of each class of stock or series thereof of the Company and the qualifications, limitations, or restrictions of
such preferences and/or rights.


 


The following abbreviations,
when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to
applicable laws or regulations:


 


	TEN
    COM	—	as
    tenants in common	 	UNIF
    GIFT MIN ACT	—	 	Custodian	 
	TEN ENT	—	as tenants
    by the entireties	 	 	 	(Cust)	 	(Minor)
	JT TEN	—	as joint tenants
    with right of survivorship and not as tenants in common	 	 	 	under
    Uniform Gifts to Minors Act

    (State)



 


Additional abbreviations may also be used though
not in the above list.


 


For value received, hereby sell, assign and transfer
unto


 


PLEASE INSERT SOCIAL SECURITY OR


 


OTHER


 


IDENTIFYING NUMBER OF ASSIGNEE


 


(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING
ZIP CODE, OF ASSIGNEE)


 


Units represented by the within
Certificate, and do hereby irrevocably constitute and appoint


 


Attorney to transfer the said
Units on the books of the within named Company with full power of substitution in the premises.


 






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Dated


 


	 	 
	 	Notice: The signature to this assignment must correspond with the name as written upon the face of the certificate in every particular, without alteration or enlargement or any change whatever.


 


Signature(s) Guaranteed:


 





	 	 	 
	THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO S.E.C. RULE 17Ad-15 (OR ANY SUCCESSOR RULE).	 	 


 


In each case, as more fully
described in the Company’s final prospectus dated [●], 2022, the holder(s) of this certificate shall be entitled to receive
a pro-rata portion of certain funds held in the trust account established in connection with the Company’s initial public offering
only in the event that (i) the Company redeems the shares of Class A common stock sold in its initial public offering and liquidates
because it does not consummate an initial business combination by [●], 2022 (or at a later date, if extended), (ii) the Company
redeems the shares of Class A common stock sold in its initial public offering in connection with a stockholder vote (x) to
amend the Company’s amended and restated certificate of incorporation to modify the substance or timing of the Company’s obligation
to redeem 100% of the Class A common stock if it does not consummate an initial business combination by [●], 2022 or (y) with
respect to any other provisions relating to stockholders’ rights or pre-initial business combination activity, or (iii) if
the holder(s) seek(s) to redeem for cash his, her or its respective shares of Class A common stock in connection with a
tender offer (or proxy solicitation, solely in the event the Company seeks stockholder approval of the proposed initial business combination)
setting forth the details of a proposed initial business combination. In no other circumstances shall the holder(s) have any right
or interest of any kind in or to the trust account.


 






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