12828
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 29960
- Proper Divisor Sum (Aliquot Sum)
- 17132
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4272
- Möbius Function
- 0
- Radical
- 6414
- 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
- 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
- no
- 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 Costas arrays of order n, counting rotations and flips as distinct.at n=12A008404
- Number of ordered 5-tuples of integers from [ 1,n ] with no common factors among triples.at n=18A015656
- Sum of maximal Dyck path prefix lengths of all 4k+3 primes in range ]2^n,2^(n+1)].at n=8A095107
- a(n) = Sum_{k=0..floor(n/2)} C(n-k,k+2)*2^(n-k-2)*(3/2)^k.at n=9A099623
- Numbers n such that 2*10^n + 6*R_n + 3 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=16A102957
- G.f.: (x^2+6*x^3+7*x^4+8*x^5+4*x^6-3*x^8-2*x^9-x^10) / ((1-x)^2*(1-x^2)^3*(1-x^3)^4*(1-x^4)).at n=13A127813
- a(n) = 101*2^(n-1) - 100.at n=7A140062
- Number of permutations of 1..n with all differences of elements separated by distances 1 through 6 being respectively unique.at n=12A170812
- Number of permutations of 1..n with all differences of elements separated by distances 1 through 7 being respectively unique.at n=12A170813
- Number of permutations of 1..n with all differences of elements separated by distances 1 through 8 being respectively unique.at n=12A170814
- Number of permutations of 1..n with all differences of elements separated by distances 1 through 9 being respectively unique.at n=12A170815
- Number of achiral combinatorial maps with n edges.at n=6A170947
- T(n,k)=Number of (n+2)X(k+2) 0..5 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock.at n=1A186570
- T(n,k)=Number of (n+2)X(k+2) 0..5 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock.at n=2A186570
- a(n) is a refactorable number and the sum of all refactorable numbers <= a(n) is also a refactorable number.at n=28A235177
- Number of (n+1) X (3+1) 0..1 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction.at n=9A250764
- Number of primitive (period n) periodic palindromic structures of length n using an infinite alphabet.at n=16A285042
- Number of non-averaging permutations of [n] with first element ceiling(n/2).at n=15A296531
- Number of partitions of n into squarefree parts that do not divide n.at n=59A300585
- Number of nonnegative solutions to (x_1)^2 + (x_2)^2 + ... + (x_6)^2 <= n.at n=40A341401