4005
domain: N
Properties
Digital Properties
- Digit Count
- 4
- 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
- 7020
- Proper Divisor Sum (Aliquot Sum)
- 3015
- 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
- 2112
- Möbius Function
- 0
- Radical
- 1335
- Omega Function (Ω)
- 4
- 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
- yes
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- yes
- 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
- 144
- Smith Number
- no
- Vampire 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
Appears in sequences
- Hexagonal numbers: a(n) = n*(2*n-1).at n=45A000384
- Some permutation of digits is a factorial number.at n=38A007926
- Some nontrivial permutation of digits is a factorial number.at n=32A007927
- Coordination sequence T1 for Zeolite Code AFR.at n=48A008019
- Expansion of Jacobi theta constant theta_2^6 /(64q^(3/2)).at n=44A008440
- a(n) = (n+1)*(n^2 +8*n +6)/6. Number of n-dimensional partitions of 4. Number of terms in 4th derivative of a function composed with itself n times.at n=26A008778
- Coordination sequence T3 for Zeolite Code RTH.at n=44A009895
- Number of unrooted quartic trees with 2n (unlabeled) nodes and possessing a bicentroid; number of 2n-carbon alkanes C(2n)H(4n+2) with a bicentroid, ignoring stereoisomers.at n=7A010373
- Odd triangular numbers.at n=44A014493
- a(n) = (2*n+1)*(4*n+1).at n=22A014634
- 2^(n-1) - n*(n+1)/2.at n=12A014846
- Binomial coefficients C(n,88).at n=2A017752
- Binomial coefficients C(90,n).at n=2A017806
- Expansion of 1/(1-x^6-x^7-x^8-x^9-x^10-x^11-x^12-x^13-x^14-x^15-x^16).at n=43A017856
- Expansion of 1/(1-x^10-x^11-x^12-x^13-x^14-x^15).at n=73A017891
- Pseudoprimes to base 8.at n=44A020137
- Pseudoprimes to base 17.at n=17A020145
- Pseudoprimes to base 44.at n=31A020172
- Pseudoprimes to base 53.at n=39A020181
- Pseudoprimes to base 71.at n=29A020199