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zipcodes.pro — ZIP/37721

37721

ZIP 37721 is Corryton, Tennessee, mostly in Knox County; area code 865; Eastern time.

Type
Standard
Time zone
America/New_York
County
Knox +1 more
Metro area
Knoxville, TN
Population
14,306
Coordinates
36.1306, -83.8149
☼ Live from 37721 — Corryton, TN

Weather right now

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Local time: —

Where 37721 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 37721
  • 🔢 Type 37721 into a pocket calculator and turn it upside down: IZLLE — not quite a word, sorry.
  • ➕ As a number, 37,721 = 67 × 563. Its digits add up to 20, a total 2,586 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1001001101011001
  • 🏠 Its numerical neighbours: 37719 (Coalfield, TN, 35 mi away) and 37722 (Cosby, TN, 41 mi away).
  • 🔄 Backwards, 37721 becomes 12773, which is not a ZIP code at all.
  • 👥 28 other ZIP codes are made of exactly the same digits (12737, 17237, 17327, 17372, 17723, 21737, …). The farthest-flung twin is 77213 in Houston, TX, 801 miles away.
  • 🧭 Farther south than 68% of all ZIP codes, and farther east than 60%.
  • 🎯843 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 37721 and you would come out at 36.13°S, 96.19°E — 1,161 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 37m of daylight. Shortest: 9h 42m.
  • 📏 At 49.3 square miles of land, 37721 is bigger than 59% of ZIP codes — room for about 37 Central Parks.
🌙 The sky over 37721 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population14,306This ZIP14,306
Households5,568This ZIP5,568
Housing units5,886This ZIP5,886
Median age43.3This ZIP43.3Tennessee38.9US 38.9
Median household income$64,892This ZIP$64,892Tennessee$69,595US $80,734
Median home value$233,300This ZIP$233,300Tennessee$286,700US $332,700
Median gross rent$973This ZIP$973Tennessee$1,189US $1,413
Bachelor's degree or higher17.8%This ZIP17.8%
Mean commute30.3 minThis ZIP30.3 min
Population density290.3 / sq miThis ZIP290.3 / sq mi

Business and tax activity

Business establishments108This ZIP108
Employees1,091This ZIP1,091
Annual payroll$41,145,000This ZIP$41,145,000
Tax returns filed6,250This ZIP6,250
Total adjusted gross income$423,582,000This ZIP$423,582,000

Land area

Land area49.28 sq miThis ZIP49.28 sq mi
Water area0.01 sq miThis ZIP0.01 sq mi

Counties 37721 spans

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

CountyShare of this ZIP
Knox County 90.1%
Union County 9.9%

Other place names in 37721

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

ZIP codes near 37721

ZIPCityDistance
37806 Mascot, TN 5.8 mi
37779 Luttrell, TN 6.4 mi
37938 Knoxville, TN 6.9 mi
37924 Knoxville, TN 7.2 mi
37918 Knoxville, TN 7.7 mi
37901 Knoxville, TN 7.8 mi
37709 Blaine, TN 8.7 mi
37807 Maynardville, TN 8.9 mi
37871 Strawberry Plains, TN 9.4 mi
37914 Knoxville, TN 10.2 mi

Find every ZIP code within 10 miles of 37721 →

Questions about this ZIP code

Where is ZIP code 37721?

37721 is in Corryton, Tennessee, in Knox County, part of the Knoxville, TN metropolitan area. Its published point location is 36.1306, -83.8149.

What county is 37721 in?

37721 spans 2 counties: Knox County and Union County. Most of it falls in Knox 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 37721?

Corryton uses area code 865, from NANPA's telephone records.

What time zone is 37721 in?

37721 uses America/New_York.

How many people live in 37721?

About 14,306 people live in ZIP code 37721, in 5,568 households, at 290.3 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 37721?

$64,892 a year, against $69,595 across Tennessee.

What ZIP codes are near 37721?

The closest are 37806 (5.8 mi), 37779 (6.4 mi), 37938 (6.9 mi), 37924 (7.2 mi) and 37918 (7.7 mi).

Is 37721 a PO Box ZIP code?

37721 is a standard ZIP code. A normal ZIP code with street delivery.

Download or cite

Cite this page

zipcodes.pro. “37721 ZIP Code — Corryton, Tennessee (Knox County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/37721

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/37721.json

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