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zipcodes.pro — ZIP/91023

91023

ZIP 91023 is Mount Wilson, California, in Los Angeles County; area code 626; Pacific time.

Type
No street area
Time zone
America/Los_Angeles
County
Los Angeles
Coordinates
34.2264, -118.0662

The Census map gives this ZIP code no delivery area of its own, which usually means it serves post office boxes, a single organization or a post office rather than streets of homes.

☼ Live from 91023 — Mount Wilson, CA

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Where 91023 is

This ZIP code has no Census tabulation area, so there is no boundary to draw — the marker is its published point location.

★ Weird and wonderful facts about 91023
  • 🔢 Type 91023 into a pocket calculator and turn it upside down: EZOIG — not quite a word, sorry.
  • ➕ As a number, 91,023 = 3 × 30341. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10110001110001111
  • 🏠 Its numerical neighbours: 91021 (Montrose, CA, 9 mi away) and 91024 (Sierra Madre, CA, 4 mi away).
  • 🔄 Backwards, 91023 becomes 32019, which is not a ZIP code at all.
  • 👥 65 other ZIP codes are made of exactly the same digits (01923, 02139, 03291, 09123, 09132, 09213, …). The farthest-flung twin is 09213 in APO AE, a military post office, 5,765 miles away.
  • 🧭 Farther south than 77% of all ZIP codes, and farther west than 91%.
  • 🎯1,140 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 91023 and you would come out at 34.23°S, 61.93°E — 1,003 miles from Saint-Denis, Reunion, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 26m of daylight. Shortest: 9h 52m.
🌙 The sky over 91023 today
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Source: USGS.

Land area

ZIP codes near 91023

ZIPCityDistance
91024 Sierra Madre, CA 3.7 mi
91003 Altadena, CA 4.5 mi
91025 Sierra Madre, CA 4.5 mi
91001 Altadena, CA 4.7 mi
91107 Pasadena, CA 4.8 mi
91104 Pasadena, CA 5.3 mi
91066 Arcadia, CA 6.2 mi
91077 Arcadia, CA 6.2 mi
91016 Monrovia, CA 6.3 mi
91017 Monrovia, CA 6.6 mi

Find every ZIP code within 10 miles of 91023 →

Questions about this ZIP code

Where is ZIP code 91023?

91023 is in Mount Wilson, California, in Los Angeles County, part of the Los Angeles-Long Beach-Anaheim, CA metropolitan area. Its published point location is 34.2264, -118.0662.

What county is 91023 in?

91023 lies in Los Angeles County.

What area code is 91023?

Mount Wilson uses area code 626, from NANPA's telephone records.

What time zone is 91023 in?

91023 uses America/Los_Angeles.

What ZIP codes are near 91023?

The closest are 91024 (3.7 mi), 91003 (4.5 mi), 91025 (4.5 mi), 91001 (4.7 mi) and 91107 (4.8 mi).

Is 91023 a PO Box ZIP code?

Possibly. The Census map gives this ZIP code no delivery area of its own, which usually means it serves post office boxes, a single organization or a post office rather than streets of homes.

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Cite this page

zipcodes.pro. “91023 ZIP Code — Mount Wilson, California (Los Angeles County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/91023

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/91023.json

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