9129
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12960
- Proper Divisor Sum (Aliquot Sum)
- 3831
- 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
- 5696
- Möbius Function
- -1
- Radical
- 9129
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 65
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
Appears in sequences
- Quadruples of different integers from [ 1,n ] with no common factors between pairs.at n=36A015623
- Eleven iterations of Reverse and Add are needed to reach a palindrome.at n=32A015992
- Number of partitions satisfying cn(1,5) + cn(4,5) <= cn(0,5) + cn(2,5) and cn(1,5) + cn(4,5) <= cn(0,5) + cn(3,5).at n=40A039864
- Partial sums of A051865.at n=17A050441
- Numbers which need eleven 'Reverse and Add' steps to reach a palindrome.at n=30A065216
- Least nontrivial multiple of the n-th prime beginning with 9.at n=40A078293
- G.f.: (1+3*x^3)/((1-x)^2*(1-x^3)^2).at n=48A092352
- a(n) = 3*(2*n^2 + 1).at n=39A097803
- a(0)=1, a(1)=1, a(n) = 5*a(n-1) + 4*a(n-2).at n=6A123270
- Variant of triangle A008301, read by rows of 2*n+1 terms, such that the first column is the secant numbers (A000364).at n=20A125053
- Central terms of triangle A125053.at n=4A125054
- Number of n X n binary arrays with all ones connected only in a 1000-1111-0010-0010 pattern in any orientation.at n=7A147170
- Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1111-0010-0010 pattern in any orientation.at n=16A147172
- Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1111-0010-0010 pattern in any orientation.at n=17A147172
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, -1), (0, 0, 1), (0, 1, 1), (1, 0, 0)}.at n=7A151044
- Number of binary strings of length n with equal numbers of 00011 and 00100 substrings.at n=14A164228
- Number of (n+1) X 3 binary arrays with rows and columns in nondecreasing order and with no 2 X 2 subblock sum differing from a horizontal or vertical neighbor subblock sum by more than one.at n=19A184064
- Left half of triangle A125053.at n=14A210111
- Number of (w,x,y,z) with all terms in {0,...,n} and w=[R/2], where R=max{w,x,y,z}-min{w,x,y,z} and [ ]=floor.at n=21A212758
- Triangle of second-order Eulerian numbers of type B.at n=19A214406