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zipcodes.pro — ZIP/66521

66521

ZIP 66521 is Onaga, Kansas, mostly in Pottawatomie County; area code 785; Central time.

Type
Standard
Time zone
America/Chicago
County
Pottawatomie +1 more
Metro area
Manhattan, KS
Population
1,417
Coordinates
39.4707, -96.2294
☼ Live from 66521 — Onaga, KS

Weather right now

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Local time: —

Where 66521 is

Approximate ZIP boundary (Census ZCTA 2020). ZIP codes are mail routes, not areas, so the shape shown is the Census tabulation area that approximates it.

★ Weird and wonderful facts about 66521
  • 🔢 Type 66521 into a pocket calculator and turn it upside down: IZSgg — not quite a word, sorry.
  • ➕ As a number, 66,521 = 7 × 13 × 17 × 43. Its digits add up to 20, a total 2,586 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10000001111011001
  • 🏠 Its numerical neighbours: 66520 (Olsburg, KS, 21 mi away) and 66522 (Oneida, KS, 31 mi away).
  • 🔄 Backwards, 66521 becomes 12566 — and that is a real ZIP code: Pine Bush, NY, 1,157 miles away.
  • 👥 31 other ZIP codes are made of exactly the same digits (12566, 15626, 15662, 16256, 16625, 16652, …). The farthest-flung twin is 12566 in Pine Bush, NY, 1,157 miles away.
  • 🧭 Farther north than 52% of all ZIP codes, and farther west than 72%.
  • 🎯127 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 66521 and you would come out at 39.47°S, 83.77°E — 953 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 57m of daylight. Shortest: 9h 23m.
  • 📏 At 177.6 square miles of land, 66521 is bigger than 89% of ZIP codes — room for about 135 Central Parks.
🌙 The sky over 66521 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population1,417This ZIP1,417
Households542This ZIP542
Housing units645This ZIP645
Median age42.8This ZIP42.8Kansas37.4US 38.9
Median household income$61,250This ZIP$61,250Kansas$74,275US $80,734
Median home value$193,000This ZIP$193,000Kansas$217,200US $332,700
Median gross rent$982This ZIP$982Kansas$1,060US $1,413
Bachelor's degree or higher27.6%This ZIP27.6%
Mean commute19.3 minThis ZIP19.3 min
Population density8.0 / sq miThis ZIP8.0 / sq mi

Business and tax activity

Business establishments35This ZIP35
Employees424This ZIP424
Annual payroll$20,130,000This ZIP$20,130,000
Tax returns filed680This ZIP680
Total adjusted gross income$45,033,000This ZIP$45,033,000

Land area

Land area177.63 sq miThis ZIP177.63 sq mi
Water area0.47 sq miThis ZIP0.47 sq mi

Counties 66521 spans

A ZIP code is a mail route and ignores county lines. Shares are by overlapping land area.

CountyShare of this ZIP
Pottawatomie County 91.6%
Nemaha County 8.4%

Other place names in 66521

Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.

ZIP codes near 66521

ZIPCityDistance
66432 Havensville, KS 8.2 mi
66549 Westmoreland, KS 11.5 mi
66422 Emmett, KS 12.2 mi
66540 Soldier, KS 13.9 mi
66426 Fostoria, KS 15.0 mi
66544 Vermillion, KS 15.2 mi
66415 Centralia, KS 15.9 mi
66417 Corning, KS 16.4 mi
66547 Wamego, KS 16.9 mi
66407 Belvue, KS 16.9 mi

Find every ZIP code within 10 miles of 66521 →

Questions about this ZIP code

Where is ZIP code 66521?

66521 is in Onaga, Kansas, in Pottawatomie County, part of the Manhattan, KS metropolitan area. Its published point location is 39.4707, -96.2294.

What county is 66521 in?

66521 spans 2 counties: Pottawatomie County and Nemaha County. Most of it falls in Pottawatomie County, measured by overlapping land area — the county holding the most land in a ZIP code is not always the one holding the most residents.

What area code is 66521?

Onaga uses area code 785, from NANPA's telephone records.

What time zone is 66521 in?

66521 uses America/Chicago.

How many people live in 66521?

About 1,417 people live in ZIP code 66521, in 542 households, at 8.0 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What is the median household income in 66521?

$61,250 a year, against $74,275 across Kansas.

What ZIP codes are near 66521?

The closest are 66432 (8.2 mi), 66549 (11.5 mi), 66422 (12.2 mi), 66540 (13.9 mi) and 66426 (15 mi).

Is 66521 a PO Box ZIP code?

66521 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “66521 ZIP Code — Onaga, Kansas (Pottawatomie County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/66521

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