7884
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 20720
- Proper Divisor Sum (Aliquot Sum)
- 12836
- 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
- 2592
- Möbius Function
- 0
- Radical
- 438
- Omega Function (Ω)
- 6
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 26
- 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
- Triangle of multi-edge stars with n edges by cyclotomic index.at n=73A010358
- Every prefix prime in base 9 (written in base 9).at n=38A024769
- a(n) = A027052(n, 2n-7).at n=8A027063
- Theta series of 6-dimensional lattice P6.4 = A6,2.at n=40A029690
- Numbers having four 0's in base 6.at n=17A043372
- When expressed in base 2 and then interpreted in base 9, is a multiple of the original number.at n=49A062850
- Numbers k such that sigma(k) = 2*usigma(k).at n=22A063880
- Numbers k such that sigma(reverse(k)) = sigma(reverse(k-1)) + sigma(reverse(k-2)).at n=13A069970
- Numbers k such that gcd(k, reverse(k)) = 27 = 3^3, where reverse(x) = A004086(x).at n=25A072016
- Triangle, read by rows, such that the diagonal (A084785) is the self-convolution of the first column (A084784) and the row sums (A084786) gives the differences of the diagonal and the first column.at n=28A084783
- Binomial transform = self-convolution: first column of the triangle (A084783).at n=7A084784
- Number of increasing subsequences that can be made from the sequence of successive numbers.at n=22A091955
- a(n) is the determinant of the 3 X 3 matrix with entries the 9 consecutive primes starting with the n-th prime.at n=26A117330
- Triangle T(n,k) read by rows: the coefficient [x^n] of x^2/(1-(k+1)*x-x^3) in row n, columns 0 <= k <= n.at n=33A117716
- a(n) = n^3 + 114 * n.at n=17A122562
- Terms of A068563 that are not terms of A124240.at n=33A124241
- The sum of the elements within a jump in a Sieve of Eratosthenes table.at n=20A179545
- Number of 4-step S, E, and NW-moving king's tours on an n X n board summed over all starting positions.at n=20A187509
- Number of meanders of order n, with 1-1 cut.at n=6A192927
- Three times second hexagonal numbers: 3*n*(2*n+1).at n=36A195319