639

639 is an odd composite number composed of two prime numbers multiplied together.

What does the number 639 look like?

This visualization shows the relationship between its 2 prime factors (large circles) and 6 divisors.

639 is an odd composite number. It is composed of two distinct prime numbers multiplied together. It has a total of six divisors.

Prime factorization of 639:

3² × 71

(3 × 3 × 71)

See below for interesting mathematical facts about the number 639 from the Numbermatics database.

Names of 639

Cardinal: 639 can be written as Six hundred thirty-nine.

Scientific notation

Scientific notation: 6.39 × 10²

Factors of 639

Number of distinct prime factors ω(n): 2
Total number of prime factors Ω(n): 3
Sum of prime factors: 74

Divisors of 639

Number of divisors d(n): 6
Complete list of divisors:
1 3 9 71 213 639
Sum of all divisors σ(n): 936
Sum of proper divisors (its aliquot sum) s(n): 297
639 is a deficient number, because the sum of its proper divisors (297) is less than itself. Its deficiency is 342

Bases of 639

Binary: 1001111111₂
Hexadecimal: 0x27F
Base-36: HR

Squares and roots of 639

639 squared (639²) is 408321
639 cubed (639³) is 260917119
The square root of 639 is 25.2784493197
The cube root of 639 is 8.6132480147

Scales and comparisons

How big is 639?

639 seconds is equal to 10 minutes, 39 seconds.
To count from 1 to 639 would take you about five minutes.

This is a very rough estimate, based on a speaking rate of half a second every third order of magnitude. If you speak quickly, you could probably say any randomly-chosen number between one and a thousand in around half a second. Very big numbers obviously take longer to say, so we add half a second for every extra x1000. (We do not count involuntary pauses, bathroom breaks or the necessity of sleep in our calculation!)
A cube with a volume of 639 cubic inches would be around 0.7 feet tall.

Recreational maths with 639

639 backwards is 936
The number of decimal digits it has is: 3
The sum of 639's digits is 18
More coming soon!

Copy this link to share with anyone:

Share this page on social media:

Link to this page

HTML: To link to this page, just copy and paste the link below into your blog, web page or email.

<a href="https://numbermatics.com/n/639/?utm_source=shared">Number 639 - Facts about the integer</a>

BBCODE: To link to this page in a forum post or comment box, just copy and paste the link code below:

[url=https://numbermatics.com/n/639/?utm_source=shared]Number 639 - Facts about the integer[/url]

Cite this page

MLA style:
"Number 639 - Facts about the integer". Numbermatics.com. 2025. Web. 20 January 2025.

APA style:
Numbermatics. (2025). Number 639 - Facts about the integer. Retrieved 20 January 2025, from https://numbermatics.com/n/639/

Chicago style:
Numbermatics. 2025. "Number 639 - Facts about the integer". https://numbermatics.com/n/639/

The information we have on file for 639 includes mathematical data and numerical statistics calculated using standard algorithms and methods. We are adding more all the time. If there are any features you would like to see, please contact us. Information provided for educational use, intellectual curiosity and fun!

Keywords: Divisors of 639, math, Factors of 639, curriculum, school, college, exams, university, Prime factorization of 639, STEM, science, technology, engineering, physics, economics, calculator, six hundred thirty-nine.