251 is a prime number. Like all primes greater than two, it is odd and has no factors apart from itself and one.

What does the number 251 look like?

As a prime, it is not composed of any other numbers and has no internal structure.

251 is a prime number. Like all primes (except two), it is an odd number.

Prime factorization of 251:


See below for interesting mathematical facts about the number 251 from the Numbermatics database.

Names of 251

  • Cardinal: 251 can be written as Two hundred fifty-one.

Scientific notation

  • Scientific notation: 2.51 × 102

Factors of 251

  • Number of distinct prime factors ω(n): 1
  • Total number of prime factors Ω(n): 1
  • Sum of prime factors: 251

Divisors of 251

  • Number of divisors d(n): 2
  • Complete list of divisors:
    1 251
  • Sum of all divisors σ(n): 252
  • Sum of proper divisors (its aliquot sum) s(n): 1
  • 251 is a deficient number, because the sum of its proper divisors (1) is less than itself. Its deficiency is 250

Bases of 251

  • Binary: 111110112
  • Hexadecimal: 0xFB
  • Base-36: 6Z

Squares and roots of 251

  • 251 squared (2512) is 63001
  • 251 cubed (2513) is 15813251
  • The square root of 251 is 15.8429795177
  • The cube root of 251 is 6.3079935487

Scales and comparisons

How big is 251?
  • 251 seconds is equal to 4 minutes, 11 seconds.
  • To count from 1 to 251 would take you about two 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 251 cubic inches would be around 0.5 feet tall.

Recreational maths with 251

  • 251 backwards is 152
  • The number of decimal digits it has is: 3
  • The sum of 251's digits is 8
  • More coming soon!

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"Number 251 - Facts about the integer". Numbermatics.com. 2024. Web. 23 June 2024.

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Numbermatics. (2024). Number 251 - Facts about the integer. Retrieved 23 June 2024, from https://numbermatics.com/n/251/

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Numbermatics. 2024. "Number 251 - Facts about the integer". https://numbermatics.com/n/251/

The information we have on file for 251 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 251, math, Factors of 251, curriculum, school, college, exams, university, Prime factorization of 251, STEM, science, technology, engineering, physics, economics, calculator, two hundred fifty-one.

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