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Where 57440 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.
- 🔢 Type 57440 into a pocket calculator and turn it upside down: OhhLS — not quite a word, sorry.
- ➕ As a number, 57,440 = 2 × 2 × 2 × 2 × 2 × 5 × 359. Its digits add up to 20, a total 2,586 other ZIP codes share.
- 💾In binary, the way a computer stores it:
1110000001100000 - 🏠 Its numerical neighbours: 57439 (Ferney, SD, 34 mi away) and 57441 (Frederick, SD, 68 mi away).
- 🔄 Backwards, 57440 becomes 04475 — and that is a real ZIP code: Passadumkeag, ME, 1,441 miles away.
- 👥 33 other ZIP codes are made of exactly the same digits (04457, 04475, 04547, 04574, 04745, 05447, …). The farthest-flung twin is 04457 in Lincoln, ME, 1,441 miles away.
- 🧭 Farther north than 90% of all ZIP codes, and farther west than 77%.
- 🎯348 miles north of the geographic center of the Lower 48, near Lebanon, Kansas.
- 🌏 Dig straight through the Earth from 57440 and you would come out at 44.85°S, 81.74°E — 624 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
- ☀Longest day of the year: 15h 36m of daylight. Shortest: 8h 47m.
- 📏 At 141.9 square miles of land, 57440 is bigger than 85% of ZIP codes — room for about 108 Central Parks.
- Working out the sun…
- Checking the USGS…
Source: USGS.
People and housing
| Population | 466This ZIP466 |
|---|---|
| Households | 122This ZIP122 |
| Housing units | 165This ZIP165 |
| Median age | 54.5This ZIP54.5South Dakota38.0US 38.9 |
| Median household income | $54,625This ZIP$54,625South Dakota$75,081US $80,734 |
| Median home value | $132,800This ZIP$132,800South Dakota$257,400US $332,700 |
| Bachelor's degree or higher | 26.5%This ZIP26.5% |
| Mean commute | 23.5 minThis ZIP23.5 min |
| Population density | 3.3 / sq miThis ZIP3.3 / sq mi |
Business and tax activity
| Business establishments | 4This ZIP4 |
|---|---|
| Employees | 9This ZIP9 |
| Annual payroll | $429,000This ZIP$429,000 |
| Tax returns filed | 220This ZIP220 |
| Total adjusted gross income | $16,129,000This ZIP$16,129,000 |
Land area
| Land area | 141.93 sq miThis ZIP141.93 sq mi |
|---|---|
| Water area | 0.69 sq miThis ZIP0.69 sq mi |
Other place names in 57440
Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.
ZIP codes near 57440
| ZIP | City | Distance |
|---|---|---|
57436 | Doland, SD | 8.9 mi |
57477 | Turton, SD | 13.6 mi |
57469 | Redfield, SD | 15.4 mi |
57258 | Raymond, SD | 16.2 mi |
57348 | Hitchcock, SD | 16.7 mi |
57424 | Ashton, SD | 17.4 mi |
57476 | Tulare, SD | 20.3 mi |
57322 | Carpenter, SD | 20.8 mi |
57429 | Brentford, SD | 21.4 mi |
57461 | Mellette, SD | 23.3 mi |
Find every ZIP code within 10 miles of 57440 →
Questions about this ZIP code
Where is ZIP code 57440?
57440 is in Frankfort, South Dakota, in Spink County. Its published point location is 44.8534, -98.2567.
What county is 57440 in?
57440 lies in Spink County.
What area code is 57440?
Frankfort uses area code 605, from NANPA's telephone records.
What time zone is 57440 in?
57440 uses America/Chicago.
How many people live in 57440?
About 466 people live in ZIP code 57440, in 122 households, at 3.3 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 57440?
$54,625 a year, against $75,081 across South Dakota.
What ZIP codes are near 57440?
The closest are 57436 (8.9 mi), 57477 (13.6 mi), 57469 (15.4 mi), 57258 (16.2 mi) and 57348 (16.7 mi).
Is 57440 a PO Box ZIP code?
57440 is a standard ZIP code. A normal ZIP code with street delivery.
Download or cite
Cite this page
zipcodes.pro. “57440 ZIP Code — Frankfort, South Dakota (Spink County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/57440
Machine-readable version of these facts:
curl https://zipcodes.pro/zip/57440.jsonUnderlying data is public domain or openly licensed — sources, vintages and licences.