1272
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 3240
- Proper Divisor Sum (Aliquot Sum)
- 1968
- 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
- 416
- Möbius Function
- 0
- Radical
- 318
- Omega Function (Ω)
- 5
- 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
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 57
- 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 solutions to the rook problem on an n X n board having a certain symmetry group (see Robinson for details).at n=9A000900
- Numbers that are the sum of 7 positive 5th powers.at n=39A003352
- Number of nonequivalent dissections of an n-gon by nonintersecting diagonals rooted at a cell up to rotation and reflection.at n=6A003456
- Numbers not of form p + 2^x + 2^y.at n=27A006286
- Number of lattice points inside circle of radius n is 4(a(n)+n)-3.at n=40A007882
- Coordination sequence for hexagonal close-packing.at n=11A007899
- Coordination sequence T1 for Zeolite Code NAT.at n=24A008203
- Coordination sequence for tridymite, lonsdaleite, and wurtzite.at n=22A008264
- If a, b in sequence, so is ab+8.at n=11A009331
- a(n) is the concatenation of n and 6n.at n=11A009440
- Coordination sequence T4 for Zeolite Code -CLO.at n=31A009853
- Coordination sequence for alpha-Nd, Position Nd1.at n=11A009948
- High-temperature expansion of Ising model susceptibility chi_4 for cubic lattice.at n=2A010046
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly three 1's.at n=19A013650
- a(n) = n*(9*n-2).at n=12A013656
- Numbers k such that phi(k) + 4 | sigma(k + 4).at n=46A015783
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite DDR = Deca-dodecasil 3R[Si120O240]qR starting with a T2 atom.at n=10A019106
- Place where n-th 1 occurs in A023117.at n=33A022779
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (F(2), F(3), ...), t = A000201 (lower Wythoff sequence).at n=14A024593
- a(1) = 2; a(n+1) = a(n)-th nonprime, where nonprimes begin at 1.at n=20A025003