Google Pixel XL has a pixel density of:
534.04

A.K.A. HTC Google Pixel XL
Released: 2016

Resolution: 2560×1440 5.5″ display

Quad HD (QHD) 2560×1440, 16:9 aspect ratio

Totaling 3.69mp (megapixels) and having a PPI of 534.04

Category: Phone
Tags: android, pixel, htc, 1440p

Pixel
Pixel XL

Codename	Sailfish (Pixel)[1] Marlin (Pixel XL)[1]
Developer	Google LLC
Manufacturer	HTC (contract manufacturer)
Series	Pixel
Model	Pixel: G-2PW4100 (North America) G-2PW4200 (International) Pixel XL: G-2PW2100 (North America) G-2PW2200 (International)
First released	October 20, 2016; 21 months ago (2016-10-20)
Availability by country	October 4, 2016  Australia Canada Germany United Kingdom United States October 13, 2016  India
Discontinued	April 11, 2018 (2018-04-11)[2]
Predecessor	Nexus 5X Nexus 6P[3]
Successor	Pixel 2 (XL)
Type	Smartphone
Form factor	Slate
Dimensions	Pixel: H: 143.8 mm (5.66 in) W: 69.5 mm (2.74 in) D: 8.5 mm (0.33 in) Pixel XL: H: 154.7 mm (6.09 in) W: 75.7 mm (2.98 in) D: 8.5 mm (0.33 in)
Weight	Pixel: 143 g (5.04 oz) Pixel XL: 168 g (5.93 oz)
Operating system	Android 7.1 “Nougat”, upgradable to Android P
System on chip	Qualcomm Snapdragon 821 (MSM8996 Pro)
CPU	Quad-core (2×2.15 GHz & 2×1.6 GHz) Kryo 64-bit ARMv8-A cores
GPU	Adreno 530
Memory	4 GB LPDDR4 RAM
Storage	32 GB or 128 GB, UFS 2.0
Battery	Pixel: 2,770 mAh Pixel XL: 3,450 mAh
Display	Pixel: 5 in (130 mm) FHD AMOLED, 1920 × 1080 (441ppi) Pixel XL: 5.5 in (140 mm) QHD AMOLED, 2560 × 1440 (534 ppi) All models: 2.5D Corning Gorilla Glass 4 100% NTSC Color Space 100000:1 contrast ratio 24-bit depth/16.77 million colours
Rear camera	12.3 MP Sony Exmor IMX378 1.55 µm pixel size f/2.0 aperture Phase-detection Autofocus + Laser Autofocus HDR+ Processing HD 720p (up to 240fps) FHD 1080p video (Up to 120 FPS) 4K 2160p video (Up to 30 FPS) Electronic Image Stabilization (Sampling gyroscope at 200 Hz)
Front camera	8 MP Sony Exmor IMX179 1.4 µm pixel size f/2.4 aperture FHD 1080p video (Up to 30 FPS)
Connectivity	North America: GSM: Quad-band GSM UMTS/WCDMA: B 1/2/4/5/8 CDMA2000: BC0/BC1/BC10 TDS-CDMA: N/A FDD LTE: B 1/2/3/4/5/7/8/12/13/17/20/25/26/28/29/30 TDD LTE: B 41 Worldwide: GSM: Quad-band GSM UMTS/WCDMA: B 1/2/4/5/6/8/9/19 CDMA2000: BC0 TDS-CDMA: B 34/39 FDD LTE: B1/2/3/4/5/7/8/12/13/17/18/19/20/21/26/28/32/ TDD LTE: B 38/39/40/41
Other	IP53 Proximity/ALS Accelerometer+Gyrometer Magnetometer Pixel Imprint (fingerprint sensor) Barometer Hall effect sensor Android Sensor Hub
Website	store.google.com/product/pixel_phone

This righthand infobox courtesy of Wikipedia.