241
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 7
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 242
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 240
- Möbius Function
- -1
- Radical
- 241
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 21
- Smith Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 53
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- zweihunderteinundvierzig· ordinal: zweihunderteinundvierzigste
- English
- two hundred forty-one· ordinal: two hundred forty-first
- Spanish
- doscientos cuarenta y uno· ordinal: 241º
- French
- deux cent quarante et un· ordinal: deux cent quarante et unième
- Italian
- duecentoquarantuno· ordinal: 241º
- Latin
- ducenti quadraginta unus· ordinal: 241.
- Portuguese
- duzentos e quarenta e um· ordinal: 241º
Appears in sequences
- Number of simple triangulations of the plane with n nodes.at n=7A000256
- Primes p of the form 3k+1 such that -sqrt(p) < sum_{x=1..p} cos(2*Pi*x^3/p) < sqrt(p).at n=7A000922
- Dimension of the n-th graded piece of the mod-2 Steenrod algebra A_2.at n=60A000929
- Lucky numbers.at n=47A000959
- n! never ends in this many 0's.at n=46A000966
- Numbers k such that sum of squares of k consecutive integers >= 1 is a square.at n=28A001032
- 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=16A001033
- Union of all numbers {p, q} where p and q are both primes or powers of primes and q = p+2.at n=48A001092
- Twin primes.at n=32A001097
- Primes with 7 as smallest primitive root.at n=2A001126
- Primes == +-1 (mod 8).at n=23A001132
- Table T(n,k) in which n-th row lists prime factors of 2^n - 1 (n >= 2), with repetition.at n=65A001265
- Table T(n,k) in which n-th row lists prime factors of 2^n + 1 (n >= 0), with repetition.at n=23A001269
- Irregular table read by rows: row n lists prime factors of 10^n + 1, with multiplicity.at n=43A001271
- Number of points in interior of n-th crystal ball in E_8 lattice.at n=1A001361
- a(n) = a(n-1) + a(n-2) + a(n-3), a(0)=3, a(1)=1, a(2)=3.at n=9A001644
- Genus of modular group Gamma(n) = genus of modular curve Chi(n).at n=19A001767
- Genus of modular group Gamma(n) = genus of modular curve Chi(n).at n=20A001767
- Expansion of (1+x^3)/((1-x)*(1-x^2)^2*(1-x^3)).at n=18A001973
- Central polygonal numbers: a(n) = n^2 - n + 1.at n=16A002061