108
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 280
- Proper Divisor Sum (Aliquot Sum)
- 172
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 36
- Möbius Function
- 0
- Radical
- 6
- Omega Function (Ω)
- 5
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 113
- 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
- yes
- Achilles Number
- yes
- Perfect Power
- no
- Smooth Number
- yes
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Names
- German
- einshundertacht· ordinal: einshundertachtste
- English
- one hundred eight· ordinal: one hundred eighth
- Spanish
- ciento ocho· ordinal: 108º
- French
- cent huit· ordinal: cent huitième
- Italian
- centootto· ordinal: 108º
- Latin
- centum octo· ordinal: 108.
- Portuguese
- cento e oito· ordinal: 108º
Appears in sequences
- Let k = p_1^e_1 p_2^e_2 p_3^e_3 ... be the prime factorization of n. Sequence gives k such that the sum of the numbers of 1's in the binary expansions of e_1, e_2, e_3, ... is odd.at n=52A000028
- Number of n-bead necklaces with 2 colors when turning over is not allowed; also number of output sequences from a simple n-stage cycling shift register; also number of binary irreducible polynomials whose degree divides n.at n=10A000031
- Generalized tangent numbers d(n,1).at n=41A000061
- Tetranacci numbers: a(n) = a(n-1) + a(n-2) + a(n-3) + a(n-4) for n >= 4 with a(0) = a(1) = a(2) = 0 and a(3) = 1.at n=11A000078
- a(n) = n^2*Product_{p|n} (1 + 1/p).at n=8A000082
- Number of free polyominoes (or square animals) with n cells.at n=7A000105
- Number of cusps of principal congruence subgroup Gamma^{hat}(n).at n=16A000114
- Lower Wythoff sequence (a Beatty sequence): a(n) = floor(n*phi), where phi = (1+sqrt(5))/2 = A001622.at n=66A000201
- a(8i+j) = 13i + a(j), where 1<=j<=8.at n=66A000202
- A Beatty sequence: floor(n*(e-1)).at n=62A000210
- a(n) = floor(n^2/3).at n=18A000212
- 3*n - 2*floor(sqrt(4*n+5)) + 5.at n=43A000277
- a(n) = a(n-1)*a(n-2).at n=4A000304
- Numbers that are the sum of 3 but no fewer nonzero squares.at n=45A000419
- a(n) is smallest number > a(n-1) of form a(i)*a(j), i < j < n.at n=11A000423
- Number of nonnegative solutions of x^2 + y^2 = z in first n shells.at n=52A000592
- Number of bicentered trees with n nodes.at n=11A000677
- Number of partitions of n into parts of 3 kinds.at n=5A000716
- Number of partitions of n in which no parts are multiples of 3.at n=17A000726
- Total number of 1's in binary expansions of 0, ..., n.at n=42A000788