171
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 260
- Proper Divisor Sum (Aliquot Sum)
- 89
- 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
- 108
- Möbius Function
- 0
- Radical
- 57
- Omega Function (Ω)
- 3
- 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
- yes
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 124
- Smith Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- einshunderteinundsiebzig· ordinal: einshunderteinundsiebzigste
- English
- one hundred seventy-one· ordinal: one hundred seventy-first
- Spanish
- ciento setenta y uno· ordinal: 171º
- French
- cent soixante-onze· ordinal: cent soixante-onzième
- Italian
- centosettantuno· ordinal: 171º
- Latin
- centum septuaginta unus· ordinal: 171.
- Portuguese
- cento e setenta e um· ordinal: 171º
Appears in sequences
- Coefficients of the 3rd-order mock theta function f(q).at n=35A000025
- Coefficient of q^(2n-1) in the series expansion of Ramanujan's mock theta function f(q).at n=17A000199
- Number of partitions into non-integral powers.at n=8A000327
- A Beatty sequence: [ n(e+1) ].at n=45A000572
- a(1)=0; for n>1, a(n) = number of isomeric hydrocarbons of the acetylene series with carbon content n.at n=9A000642
- An approximation to population of x^2 + y^2 <= 2^n.at n=9A000692
- Dimension of the n-th graded piece of the mod-2 Steenrod algebra A_2.at n=53A000929
- Lucky numbers.at n=35A000959
- Jacobsthal sequence (or Jacobsthal numbers): a(n) = a(n-1) + 2*a(n-2), with a(0) = 0, a(1) = 1; also a(n) = nearest integer to 2^n/3.at n=9A001045
- Dimensions (sorted, with duplicates removed) of real simple Lie algebras.at n=43A001066
- Numbers m such that Sum_{k=0..m-1} exp(2*Pi*i*k^3/m) != 0.at n=46A001074
- Moran numbers: k such that k/(sum of digits of k) is prime.at n=14A001101
- A self-generating sequence: a(1)=1, a(2)=2, a(n+1) chosen so that a(n+1)-a(n-1) is the first number not obtainable as a(j)-a(i) for 1<=i<j<=n.at n=17A001149
- A Fielder sequence: a(n) = a(n-1) + a(n-2) - a(n-6), n >= 7.at n=11A001635
- Numbers whose digits contain no loops (version 2).at n=50A001742
- Sorting numbers: number of comparisons for merge insertion sort of n elements.at n=41A001768
- Related to Zarankiewicz's problem.at n=16A001841
- Sorting numbers: maximal number of comparisons for sorting n elements by binary insertion.at n=38A001855
- v-pile positions of the 4-Wythoff game with i=3.at n=32A001968
- Nearest integer to n^2/8.at n=37A001971