TYPO3 12: Set TypoScript constant as integer

So I'm currently updating a TYPO3 website from v11 to v12 and I've run into a problem I can't seem to fix. In my fluid template I'm generating a filter form using AJAX. To do that I'm assigning the AJAX PageType to the form. Since the number I'm setting is used in multiple places, I have a constant defined for it.

Since updating to TYPO3 12 I'm getting the following error:

TYPO3\CMS\Extbase\Mvc\Web\Routing\UriBuilder::setTargetPageType(): Argument #1 ($targetPageType) must be of type int, string given

Here's part of my code:
HTML

<f:form action="list" method="GET" name="overwriteDemand" pageType="{settings.tx_t8_references_ajaxpage}">

TypoScript constant

plugin.tx_t8references {    ajaxPage = 427592}

TypoScript setup

plugin.tx_t8references {    settings {        tx_t8_references_ajaxpage = {$plugin.tx_t8references.ajaxPage}    }}

Here's the output I get when using <f:debug>{settings.tx_t8_references_ajaxpage}</f:debug>:

How can I make it so that the constant I've set is of type integer?

Any help is appreciated, thank you in advance.