Are you using the main query or a custom WP_Query for displaying the posts?
If so :
$wp_query->found_posts; //Main query
$wp_query->current_post; // current post index
or
$my_wp_query->found_posts; //custom wp_query object - total found posts
$my_wp_query->current_post; // current post index
So, example
if( have_posts() ) : while( have_posts() ) : the_post();
?>
<p>The post <?php the_title(); ?> is <?php echo $wp_query->current_post; ?>th of <?php echo $wp_query->found_posts; ?> in category <?php echo 'your cat here'; ?></p>
<?php endwhile; endif; ?>