7988
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 32
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 13986
- Proper Divisor Sum (Aliquot Sum)
- 5998
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3992
- Möbius Function
- 0
- Radical
- 3994
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 2
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
- 52
- 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
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite EUO = EU-1 Nan[AlnSi112-nO224] starting with a T1 atom.at n=12A019127
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite YUG = Yugawaralite Ca2[Al4Si12O32].8H2O starting at a T1 atom.at n=12A019264
- Expansion of 1/((1-x)(1-7x)(1-9x)(1-11x)).at n=3A024442
- Sum of digits = 8 times number of digits.at n=22A061425
- Numbers k such that prime(k) + prime(k+1)*2 is a square.at n=17A064504
- Partial sums of A068058 + 1.at n=37A068059
- a(n) = smallest multiple of 4 with sum of digits = n.at n=31A077489
- a(n) is the largest number such that all of a(n)'s length-n substrings are distinct and divisible by 38.at n=2A093238
- a(n) = 997*n + 1009.at n=7A100776
- Numbers n such that 6*10^n + R_n + 6 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=8A103028
- Numbers n such that Lucas(prime(n)) is prime, where Lucas = A000032.at n=39A120561
- Triangle, read by rows of 2n+1 terms, where T(n,k) = T(n,k-1) + T(n-1,k-2) for n>0, 1<k<=2n, with T(n,1)=T(n,0)=T(n-1,2n-2) for n>0 and T(0,0)=1.at n=56A132427
- Central terms of triangle A132427.at n=7A132428
- Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,1 4,1 5,1 polyhexes in any orientation on a planar nXnXn triangular grid.at n=6A155296
- The initial decimal digits of 2^a(n) are the decimal digits of n followed by n.at n=41A171652
- Number of strings of numbers x(i=1..4) in 0..n with sum i*x(i) equal to n*4.at n=32A184704
- T(n,k)=Number of (n+1)X(k+1) 0..5 arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors.at n=3A186486
- T(n,k)=Number of (n+1)X(k+1) 0..5 arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors.at n=5A186486
- T(n,m)=Number of (n+1)X2 0..m arrays with every 2X2 subblock commuting with each of its vertical 2X2 subblock neighbors.at n=23A187363
- T(n,m)=Number of (n+1)X4 0..m arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors.at n=10A188058