2040
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 6
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 32
- Divisor Sum
- 6480
- Proper Divisor Sum (Aliquot Sum)
- 4440
- 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
- 512
- Möbius Function
- 0
- Radical
- 510
- 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
- no
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 50
- 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
- Number of ways of writing n as a sum of 6 squares.at n=13A000141
- Number of n X n matrices with exactly 2 1's in each row and column, other entries 0.at n=5A001499
- Number of n X n 0-1 matrices with all column and row sums equal to 3.at n=5A001501
- Expansion of (1/theta_4(q)^2 -1)/4 in powers of q.at n=10A002318
- Number of n-step closed paths on hexagonal lattice.at n=6A002898
- a(n) = n^2 + prime(n).at n=42A004232
- 'Eban' numbers (the letter 'e' is banned!).at n=27A006933
- McKay-Thompson series of class 5a for Monster.at n=19A007253
- Coordination sequence for D_4 lattice.at n=5A007900
- Some permutation of digits is a factorial number.at n=32A007926
- Some nontrivial permutation of digits is a factorial number.at n=26A007927
- Coordination sequence T2 for Zeolite Code MEL.at n=29A008151
- Triangle read by rows: T(n,k) (n >= 0, 0 <= k <= n) gives number of {0,1} n X n matrices with all row and column sums equal to k.at n=18A008300
- Triangle read by rows: T(n,k) (n >= 0, 0 <= k <= n) gives number of {0,1} n X n matrices with all row and column sums equal to k.at n=17A008300
- Theta series of {D_6}* lattice.at n=26A008425
- High-temperature coefficients for 6-d cubic lattice.at n=2A010574
- a(n) = floor(n*(n-1)*(n-2)/21).at n=36A011903
- a(n) = floor( n*(n-1)*(n-2)*(n-3)/28 ).at n=17A011938
- Number of Barlow packings with group P63/mmc(S) that repeat after 4n layers.at n=11A011946
- Four-fold exponential convolution of Fibonacci numbers with themselves.at n=6A014340