189
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 320
- Proper Divisor Sum (Aliquot Sum)
- 131
- 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
- 21
- Omega Function (Ω)
- 4
- 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
- 106
- 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
- einshundertneunundachtzig· ordinal: einshundertneunundachtzigste
- English
- one hundred eighty-nine· ordinal: one hundred eighty-ninth
- Spanish
- ciento ochenta y nueve· ordinal: 189º
- French
- cent quatre-vingt-neuf· ordinal: cent quatre-vingt-neufième
- Italian
- centoottantanove· ordinal: 189º
- Latin
- centum octoginta novem· ordinal: 189.
- Portuguese
- cento e oitenta e nove· ordinal: 189º
Appears in sequences
- Number of primitive n-bead necklaces (turning over is allowed) where complements are equivalent.at n=13A000046
- a(n) = floor(n^(3/2)).at n=33A000093
- a(n) = n*(n+3)/2.at n=18A000096
- Number of bipartite partitions of n white objects and 4 black ones.at n=5A000465
- Number of bipartite partitions of n white objects and 5 black ones.at n=4A000491
- Heptagonal numbers (or 7-gonal numbers): n*(5*n-3)/2.at n=9A000566
- A Beatty sequence: [ n(e+1) ].at n=50A000572
- Narayana's cows sequence: a(0) = a(1) = a(2) = 1; thereafter a(n) = a(n-1) + a(n-3).at n=15A000930
- Lucky numbers.at n=36A000959
- Numbers m such that Sum_{k=0..m-1} exp(2*Pi*i*k^3/m) != 0.at n=50A001074
- Related to Gilbreath conjecture.at n=9A001549
- Sorting numbers: number of comparisons for merge insertion sort of n elements.at n=44A001768
- Numbers k such that 19*2^k - 1 is prime.at n=10A001775
- n-phi-torial, or phi-torial of n: Product k, 1 <= k <= n, k relatively prime to n.at n=9A001783
- Sorting numbers: maximal number of comparisons for sorting n elements by binary insertion.at n=41A001855
- a(n) = floor((n+1/2)*(2+sqrt(2))); winning positions in the 2-Wythoff game.at n=55A001954
- Beatty sequence of (5+sqrt(13))/2.at n=43A001956
- v-pile positions of the 4-Wythoff game with i=1.at n=36A001964
- Numbers k for which the rank of the elliptic curve y^2 = x^3 - k*x is 0.at n=65A002156
- Numbers k such that 45*2^k - 1 is prime.at n=23A002242