249
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 336
- Proper Divisor Sum (Aliquot Sum)
- 87
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 164
- Möbius Function
- 1
- Radical
- 249
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 47
- Smith Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- zweihundertneunundvierzig· ordinal: zweihundertneunundvierzigste
- English
- two hundred forty-nine· ordinal: two hundred forty-ninth
- Spanish
- doscientos cuarenta y nueve· ordinal: 249º
- French
- deux cent quarante-neuf· ordinal: deux cent quarante-neufième
- Italian
- duecentoquarantanove· ordinal: 249º
- Latin
- ducenti quadraginta novem· ordinal: 249.
- Portuguese
- duzentos e quarenta e nove· ordinal: 249º
Appears in sequences
- Number of series-reduced trees with n nodes.at n=16A000014
- Number of tertiary alcohols (alkanols or alkyl alcohols C_n H_{2n+1} OH) with n carbon atoms.at n=11A000600
- Number of esters with n carbon atoms up to structural isomerism.at n=7A000632
- EULER transform of 3, 2, 2, 2, 2, 2, 2, 2, ...at n=7A000713
- Numbers k such that sum of squares of k consecutive integers >= 1 is a square.at n=30A001032
- Numbers n such that the sum of the squares of n consecutive positive odd numbers x^2 + (x+2)^2 + ... + (x+2n-2)^2 = k^2 for some integer k. The least values of x and k for each n are in A056131 and A056132, respectively.at n=18A001033
- Number of ways of making change for n cents using coins of 1, 2, 5, 10, 20, 50 cents.at n=41A001313
- Number of partitions of n into at most 4 parts.at n=28A001400
- Nearest integer to 2*n*log(n).at n=35A001618
- a(n) = ceiling(sqrt( 2*Pi )^n).at n=6A001698
- a(n) = 3 * prime(n).at n=22A001748
- Sorting numbers: number of comparisons for merge insertion sort of n elements.at n=54A001768
- Sorting numbers: maximal number of comparisons for sorting n elements by binary insertion.at n=51A001855
- Denominators of cosecant numbers: -2*(2^(2*n-1)-1)*Bernoulli(2*n).at n=41A001897
- Beatty sequence of (5+sqrt(13))/2.at n=57A001956
- Number of partitions of floor(5n/2)-1 into n nonnegative integers each no more than 5.at n=12A001976
- Numbers k for which the rank of the elliptic curve y^2 = x^3 - k is 2.at n=33A002154
- Least number k such that phi(k) = m, where m runs through the values (A002202) taken by phi.at n=59A002181
- Numbers k such that the Woodall number k*2^k - 1 is prime.at n=8A002234
- Numbers of the form (p^2 - 49)/120 where p is prime.at n=20A002382