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zipcodes.pro — ZIP/57787

57787

ZIP 57787 is Union Center, South Dakota, in Meade County; area code 605; Mountain time.

Type
Standard
Time zone
America/Denver
County
Meade
Metro area
Rapid City, SD
Population
487
Coordinates
44.6680, -102.6578
☼ Live from 57787 — Union Center, SD

Weather right now

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Local time: —

Where 57787 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 57787
  • 🔢 Type 57787 into a pocket calculator and turn it upside down: LBLLS — not quite a word, sorry.
  • ➕ 57787 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 34, a total 322 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1110000110111011
  • 🏠 Its numerical neighbours: 57785 (Sturgis, SD, 32 mi away) and 57788 (Vale, SD, 27 mi away).
  • 🔄 Backwards, 57787 becomes 78775, which is not a ZIP code at all.
  • 👥 8 other ZIP codes are made of exactly the same digits (75778, 77578, 77587, 77857, 77875, 78577, …). The farthest-flung twin is 78577 in Pharr, TX, 1,302 miles away.
  • 🧭 Farther north than 90% of all ZIP codes, and farther west than 81%.
  • 🎯394 miles northwest of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 57787 and you would come out at 44.67°S, 77.34°E — 466 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 34m of daylight. Shortest: 8h 48m.
  • 📏 At 627.2 square miles of land, 57787 is bigger than 98% of ZIP codes — room for about 476 Central Parks.
🌙 The sky over 57787 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population487This ZIP487
Households200This ZIP200
Housing units200This ZIP200
Median age36.7This ZIP36.7South Dakota38.0US 38.9
Median household income$53,750This ZIP$53,750South Dakota$75,081US $80,734
Median home value$61,800This ZIP$61,800South Dakota$257,400US $332,700
Median gross rent$952This ZIP$952South Dakota$946US $1,413
Bachelor's degree or higher35.9%This ZIP35.9%
Mean commute14.3 minThis ZIP14.3 min
Population density0.8 / sq miThis ZIP0.8 / sq mi

Business and tax activity

Business establishments4This ZIP4
Employees28This ZIP28
Annual payroll$1,709,000This ZIP$1,709,000
Tax returns filed140This ZIP140
Total adjusted gross income$9,354,000This ZIP$9,354,000

Land area

Land area627.24 sq miThis ZIP627.24 sq mi
Water area0.98 sq miThis ZIP0.98 sq mi

ZIP codes near 57787

ZIPCityDistance
57737 Enning, SD 10.4 mi
57792 White Owl, SD 15.1 mi
57758 Mud Butte, SD 22.9 mi
57788 Vale, SD 27.1 mi
57791 Wasta, SD 30.7 mi
57761 New Underwood, SD 31.1 mi
57785 Sturgis, SD 31.9 mi
57748 Howes, SD 32.3 mi
57626 Faith, SD 32.8 mi
57719 Box Elder, SD 34.4 mi

Find every ZIP code within 10 miles of 57787 →

Questions about this ZIP code

Where is ZIP code 57787?

57787 is in Union Center, South Dakota, in Meade County, part of the Rapid City, SD metropolitan area. Its published point location is 44.6680, -102.6578.

What county is 57787 in?

57787 lies in Meade County.

What area code is 57787?

Union Center uses area code 605, from NANPA's telephone records.

What time zone is 57787 in?

57787 uses America/Denver.

How many people live in 57787?

About 487 people live in ZIP code 57787, in 200 households, at 0.8 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 57787?

$53,750 a year, against $75,081 across South Dakota.

What ZIP codes are near 57787?

The closest are 57737 (10.4 mi), 57792 (15.1 mi), 57758 (22.9 mi), 57788 (27.1 mi) and 57791 (30.7 mi).

Is 57787 a PO Box ZIP code?

57787 is a standard ZIP code. A normal ZIP code with street delivery.

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zipcodes.pro. “57787 ZIP Code — Union Center, South Dakota (Meade County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/57787

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