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zipcodes.pro — ZIP/21664

21664

ZIP 21664 is Secretary, Maryland, in Dorchester County; area codes 667 and 410; Eastern time.

Type
Standard
Time zone
America/New_York
County
Dorchester
Metro area
Cambridge, MD
Population
635
Coordinates
38.6076, -75.9471
☼ Live from 21664 — Secretary, MD

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Local time: —

Where 21664 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 21664
  • 🔢 Type 21664 into a pocket calculator and turn it upside down: hggIZ — not quite a word, sorry.
  • ➕ As a number, 21,664 = 2 × 2 × 2 × 2 × 2 × 677. Its digits add up to 19, a total 2,454 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101010010100000
  • 🏠 Its numerical neighbours: 21663 (Saint Michaels, MD, 20 mi away) and 21665 (Sherwood, MD, 25 mi away).
  • 🔄 Backwards, 21664 becomes 46612, which is not a ZIP code at all.
  • 👥 20 other ZIP codes are made of exactly the same digits (12466, 14626, 16246, 16426, 16624, 26146, …). The farthest-flung twin is 66412 in Bremen, KS, 1,115 miles away.
  • 🧭 Farther south than 54% of all ZIP codes, and farther east than 85%.
  • 🎯1,211 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21664 and you would come out at 38.61°S, 104.05°E — 808 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 52m of daylight. Shortest: 9h 28m.
  • 📏 At 0.291 square miles of land, 21664 is bigger than 3% of ZIP codes — about 141 football fields.
🌙 The sky over 21664 today
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🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population635This ZIP635
Households217This ZIP217
Housing units257This ZIP257
Median age34.0This ZIP34.0Maryland39.4US 38.9
Median household income$82,721This ZIP$82,721Maryland$103,678US $80,734
Median home value$172,000This ZIP$172,000Maryland$419,900US $332,700
Median gross rent$1,175This ZIP$1,175Maryland$1,705US $1,413
Bachelor's degree or higher20.3%This ZIP20.3%
Mean commute25.4 minThis ZIP25.4 min
Population density2,182.1 / sq miThis ZIP2,182.1 / sq mi

Business and tax activity

Business establishments12This ZIP12
Employees58This ZIP58
Annual payroll$2,969,000This ZIP$2,969,000

Land area

Land area0.29 sq miThis ZIP0.29 sq mi
Water area0.02 sq miThis ZIP0.02 sq mi

Other place names in 21664

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

ZIP codes near 21664

ZIPCityDistance
21631 East New Market, MD 1.8 mi
21643 Hurlock, MD 4.9 mi
21835 Linkwood, MD 5.1 mi
21673 Trappe, MD 5.7 mi
21659 Rhodesdale, MD 8.2 mi
21609 Bethlehem, MD 9.2 mi
21655 Preston, MD 9.7 mi
21613 Cambridge, MD 10.2 mi
21654 Oxford, MD 11.5 mi
21632 Federalsburg, MD 12.7 mi

Find every ZIP code within 10 miles of 21664 →

Questions about this ZIP code

Where is ZIP code 21664?

21664 is in Secretary, Maryland, in Dorchester County, part of the Cambridge, MD micropolitan area. Its published point location is 38.6076, -75.9471.

What county is 21664 in?

21664 lies in Dorchester County.

What area code is 21664?

Secretary uses area codes 667 and 410, from NANPA's telephone records.

What time zone is 21664 in?

21664 uses America/New_York.

How many people live in 21664?

About 635 people live in ZIP code 21664, in 217 households, at 2,182.1 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 21664?

$82,721 a year, against $103,678 across Maryland.

What ZIP codes are near 21664?

The closest are 21631 (1.8 mi), 21643 (4.9 mi), 21835 (5.1 mi), 21673 (5.7 mi) and 21659 (8.2 mi).

Is 21664 a PO Box ZIP code?

21664 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21664 ZIP Code — Secretary, Maryland (Dorchester County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21664

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