1980
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 6552
- Proper Divisor Sum (Aliquot Sum)
- 4572
- 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
- 480
- Möbius Function
- 0
- Radical
- 330
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 4
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
- yes
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 99
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = (n+1)*(n+3)*(n+8)/6.at n=20A000297
- Number of ways of folding a 2 X n strip of stamps.at n=5A001415
- Bessel polynomial {y_n}''(1).at n=4A001516
- A self-generating sequence: every positive integer occurs as a(i)-a(j) for a unique pair i,j.at n=16A001856
- Highly abundant numbers: numbers k such that sigma(k) > sigma(m) for all m < k.at n=53A002093
- Oblong (or promic, pronic, or heteromecic) numbers: a(n) = n*(n+1).at n=44A002378
- Number of tree-rooted bridgeless planar maps with two vertices and n faces.at n=7A002740
- a(n) = 2*n*(2*n+1).at n=22A002943
- a(n) = (3^n/n!) * Product_{k=0..n-1} (3*k + 5).at n=3A004992
- Denominators of Cauchy numbers of first type.at n=20A006233
- Number of connected regular bipartite graphs of degree 4 with 2n nodes.at n=5A006824
- Successive integers produced by Conway's PRIMEGAME.at n=32A007542
- a(n) = n OR n^2 (applied to binary expansions).at n=43A007745
- Coordination sequence T4 for Zeolite Code HEU.at n=29A008119
- Coordination sequence for quartz.at n=25A008261
- Triangle read by rows: T(n,k) is the number of simple regular connected bipartite graphs with 2n nodes and degree k, (2 <= k <= n).at n=30A008326
- Theta series of A_10 lattice.at n=2A008450
- Orders of non-cyclic simple groups (divided by 4).at n=14A008976
- Expansion of e.g.f. log(1+x)/exp(tanh(x)).at n=7A009439
- Coordination sequence T4 for Zeolite Code VET.at n=27A009905