7112
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 15360
- Proper Divisor Sum (Aliquot Sum)
- 8248
- 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
- 3024
- Möbius Function
- 0
- Radical
- 1778
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 150
- 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) = prime(n)*(prime(n-1)-1)/2.at n=28A014302
- Numbers whose set of base-13 digits is {1,3}.at n=26A032920
- Every run of digits of n in base 13 has length 2.at n=37A033011
- Composite numbers k such that digits in k and in juxtaposition of prime factors of k are the same (apart from multiplicity).at n=12A035141
- Number of partitions satisfying (cn(2,5) = cn(3,5) and cn(0,5) <= cn(1,5) and cn(0,5) <= cn(4,5)).at n=44A036805
- a(n)=(s(n)+3)/10, where s(n)=n-th base 10 palindrome that starts with 7.at n=33A043086
- Positive integers having more base-13 runs of even length than odd.at n=39A044839
- Number of ways to cover (without overlapping) a ring lattice (necklace) of n sites with molecules that are 7 sites wide.at n=38A058366
- Binomial transform of A002024.at n=11A065979
- Number of functions from [1,2,...,n] to [1,2,...,n] such that the image contains exactly two elements.at n=6A068605
- Multiples of 7 in which there is no common digit in successive terms.at n=21A083495
- Self-convolution of A086582; the first 2^n terms of this sequence gives the 2^n terms that follow the 2^n-th term of A086582.at n=39A086583
- Triangle read by rows: T(n,k) = number of functions from [1,2,...,n] to [1,2,...,n] such that the image contains exactly k elements (0<=k<=n).at n=38A090657
- Second inverse mod 2 binomial transform of 2^n.at n=7A101554
- Triangle read by rows: T(n,h) = number of functions f:{1,2,...,n}->{1,2,...,n} such that |Image(f)|=h; h=1,2,...,n, n=1,2,3,... . Essentially A090657, but without zeros.at n=29A101817
- G.f.: Product_{i>=1} (1 - 2*(-x)^i)/(1 - (-x)^i)^2.at n=38A104510
- a(n)= a(n-1) +3*a(n-2) -3*a(n-4).at n=14A107384
- Indices n such that the 3 X 3 matrix with components (row by row) prime(n+k), 0 <= k <= 8, has zero determinant.at n=11A117345
- Riordan array ((1-x+sqrt(1-6x+x^2))/2, (1+x-sqrt(1-6x+x^2))/4).at n=58A117354
- a(n) = n*(9*n+2).at n=28A147296