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zipcodes.pro — ZIP/57646

57646

ZIP 57646 is Mound City, South Dakota, in Campbell County; area code 605; Central time.

Type
Standard
Time zone
America/Chicago
County
Campbell
Metro area
none
Population
272
Coordinates
45.6805, -100.0582
☼ Live from 57646 — Mound City, SD

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Local time: —

Where 57646 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 57646
  • 🔢 Type 57646 into a pocket calculator and turn it upside down: ghgLS — not quite a word, sorry.
  • ➕ As a number, 57,646 = 2 × 19 × 37 × 41. Its digits add up to 28, a total 1,520 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1110000100101110
  • 🏠 Its numerical neighbours: 57645 (Morristown, SD, 81 mi away) and 57648 (Pollock, SD, 21 mi away).
  • 🔄 Backwards, 57646 becomes 64675, which is not a ZIP code at all.
  • 👥 27 other ZIP codes are made of exactly the same digits (45766, 46567, 46765, 47665, 54667, 54766, …). The farthest-flung twin is 76564 in Pendleton, TX, 1,011 miles away.
  • 🧭 Farther north than 93% of all ZIP codes, and farther west than 80%.
  • 🎯411 miles north of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 57646 and you would come out at 45.68°S, 79.94°E — 519 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 43m of daylight. Shortest: 8h 41m.
  • 📏 At 128.4 square miles of land, 57646 is bigger than 83% of ZIP codes — room for about 97 Central Parks.
🌙 The sky over 57646 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population272This ZIP272
Households109This ZIP109
Housing units143This ZIP143
Median age37.5This ZIP37.5South Dakota38.0US 38.9
Median household income$101,406This ZIP$101,406South Dakota$75,081US $80,734
Median home value$113,300This ZIP$113,300South Dakota$257,400US $332,700
Bachelor's degree or higher47.0%This ZIP47.0%
Mean commute21.0 minThis ZIP21.0 min
Population density2.1 / sq miThis ZIP2.1 / sq mi

Business and tax activity

Business establishments4This ZIP4
Employees34This ZIP34
Annual payroll$262,000This ZIP$262,000
Tax returns filed110This ZIP110
Total adjusted gross income$11,744,000This ZIP$11,744,000

Land area

Land area128.41 sq miThis ZIP128.41 sq mi
Water area0.59 sq miThis ZIP0.59 sq mi

Other place names in 57646

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

ZIP codes near 57646

ZIPCityDistance
57632 Herreid, SD 10.6 mi
57631 Glenham, SD 13.1 mi
57452 Java, SD 14.1 mi
57472 Selby, SD 17.6 mi
57648 Pollock, SD 21.3 mi
57437 Eureka, SD 22.2 mi
57428 Bowdle, SD 24.3 mi
57658 Wakpala, SD 24.3 mi
58542 Hague, ND 25.4 mi
57420 Akaska, SD 27.8 mi

Find every ZIP code within 10 miles of 57646 →

Questions about this ZIP code

Where is ZIP code 57646?

57646 is in Mound City, South Dakota, in Campbell County. Its published point location is 45.6805, -100.0582.

What county is 57646 in?

57646 lies in Campbell County.

What area code is 57646?

Mound City uses area code 605, from NANPA's telephone records.

What time zone is 57646 in?

57646 uses America/Chicago.

How many people live in 57646?

About 272 people live in ZIP code 57646, in 109 households, at 2.1 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 57646?

$101,406 a year, against $75,081 across South Dakota.

What ZIP codes are near 57646?

The closest are 57632 (10.6 mi), 57631 (13.1 mi), 57452 (14.1 mi), 57472 (17.6 mi) and 57648 (21.3 mi).

Is 57646 a PO Box ZIP code?

57646 is a standard ZIP code. A normal ZIP code with street delivery.

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zipcodes.pro. “57646 ZIP Code — Mound City, South Dakota (Campbell County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/57646

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