مشکل در pagination

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صفحه بندی کار میکنه فقط مشکلی که داره اگه یه حرفی کنار صفحه قرار بگیره

index.php?page=1aaaaa

خطا Notice: A non well formed numeric value encountered in میده

<?php
if(isset($_GET['page']) && !empty($_GET['page'])){
$page = $_GET['page'];
} else {
$page = 1;
}
$limit = 24;
$start = ($page - 1) * $limit;

$next = $page + 1;
$previous = $page-1;

$query_count = $conn->prepare("SELECT id FROM post");
$query_count->execute();
$total_data = $query_count->rowCount();
$total_page = ceil($total_data / $limit);

$stmt = $conn->prepare("SELECT * FROM post LIMIT $start ,$limit");
$stmt->execute();
$result= $stmt->fetchAll(PDO::FETCH_ASSOC);
?>
.
.
article
.
.
<nav aria-label="Page navigation">
  <ul class="pagination justify-content-center mt-5">
<li class="page-item"><a class="page-link" href="https://roocket.ir/index.php?page=<?php echo $previous ?>">قبلی</a></li>
<?php
for ($i = 1; $i<= $total_page; $i++) {      
?>
<li class="page-item"><a class="page-link <?php echo $i == $page ? 'active': '' ?>" href="https://roocket.ir/index.php?page=<?php echo $i ?>"><?php echo $i ?></a></li>
<?php
}
?>
<li class="page-item"><a class="page-link" href="https://roocket.ir/index.php?page=<?php echo $next ?>">بعدی</a></li>
  </ul>
</nav>

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