Index: src/wp-admin/includes/media.php
===================================================================
--- src/wp-admin/includes/media.php	(revision 58166)
+++ src/wp-admin/includes/media.php	(working copy)
@@ -1664,7 +1664,8 @@
 	$meta       = wp_get_attachment_metadata( $post->ID );
 
 	if ( isset( $meta['width'], $meta['height'] ) ) {
-		$media_dims .= "<span id='media-dims-$post->ID'>{$meta['width']}&nbsp;&times;&nbsp;{$meta['height']}</span> ";
+		/* translators: 1: A number of pixels wide, 2: A number of pixels tall. */
+		$media_dims .= "<span id='media-dims-$post->ID'>" . sprintf( __( '%1$s by %2$s pixels' ), $meta['width'], $meta['height'] ) . '</span>';
 	}
 
 	/**
@@ -3306,7 +3307,8 @@
 	$meta       = wp_get_attachment_metadata( $attachment_id );
 
 	if ( isset( $meta['width'], $meta['height'] ) ) {
-		$media_dims .= "<span id='media-dims-$attachment_id'>{$meta['width']}&nbsp;&times;&nbsp;{$meta['height']}</span> ";
+		/* translators: 1: A number of pixels wide, 2: A number of pixels tall. */
+		$media_dims .= "<span id='media-dims-$attachment_id'>" . sprintf( __( '%1$s by %2$s pixels' ), $meta['width'], $meta['height'] ) . '</span>';
 	}
 	/** This filter is documented in wp-admin/includes/media.php */
 	$media_dims = apply_filters( 'media_meta', $media_dims, $post );
@@ -3441,6 +3443,9 @@
 							echo ' ' . strtoupper( esc_html( $meta['bitrate_mode'] ) );
 						}
 						break;
+					case 'length_formatted':
+						echo human_readable_duration( $meta['length_formatted'] );
+						break;
 					default:
 						echo esc_html( $meta[ $key ] );
 						break;
Index: src/wp-includes/media-template.php
===================================================================
--- src/wp-includes/media-template.php	(revision 58166)
+++ src/wp-includes/media-template.php	(working copy)
@@ -483,7 +483,7 @@
 
 				<# if ( data.fileLength && data.fileLengthHumanReadable ) { #>
 					<div class="file-length"><strong><?php _e( 'Length:' ); ?></strong>
-						<span aria-hidden="true">{{ data.fileLength }}</span>
+						<span aria-hidden="true">{{ data.fileLengthHumanReadable }}</span>
 						<span class="screen-reader-text">{{ data.fileLengthHumanReadable }}</span>
 					</div>
 				<# } #>
@@ -729,7 +729,7 @@
 
 				<# if ( data.fileLength && data.fileLengthHumanReadable ) { #>
 					<div class="file-length"><?php _e( 'Length:' ); ?>
-						<span aria-hidden="true">{{ data.fileLength }}</span>
+						<span aria-hidden="true">{{ data.fileLengthHumanReadable }}</span>
 						<span class="screen-reader-text">{{ data.fileLengthHumanReadable }}</span>
 					</div>
 				<# } #>