9042
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 19872
- Proper Divisor Sum (Aliquot Sum)
- 10830
- 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
- 2720
- Möbius Function
- 1
- Radical
- 9042
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- 184
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- yes
- 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 binary partitions: number of partitions of 2n into powers of 2.at n=49A000123
- Coefficient of x^7 in expansion of (1+x+x^2)^n.at n=7A005715
- Form array in which n-th row is obtained by expanding (1 + x + x^2)^n and taking the 4th column from the center.at n=7A014533
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 94.at n=16A031592
- McKay-Thompson series of class 40C for Monster.at n=45A058664
- At these values of k the first, 2nd and 3rd cyclotomic polynomials all give prime numbers.at n=33A070020
- Number of primes less than or equal to Pi^n.at n=10A071973
- Number of binary strings with n 1's and n 0's avoiding zigzags, that is avoiding the substrings 101 and 010.at n=11A078678
- Number of primes between n^2 and n^3.at n=46A079648
- Number of partitions of n such that the number of different parts is odd.at n=35A090794
- Number of partitions of n into parts which are not digits of n in decimal representation.at n=43A136460
- Numbers k such that both k and k^2/2 are averages of twin prime pairs.at n=16A152787
- Averages of twin prime pairs of A154546.at n=34A154548
- Numbers k such that k-1, k+1, and k^2-k-1 are primes.at n=32A154666
- Let n be the number whose square n^2 has the decimal expansion { d(1) d(2) ... d(D) }, and let q be the corresponding number whose decimal expansion is { d(2) d(3) ... d(D) d(1)}. Sequence lists numbers n dividing q.at n=41A177928
- Triangle T(n,k) with the coefficient [x^k] of the series (1-x)^(n+1) * Sum_{j>=0} binomial(n+3*j,3*j)*x^j, in row n, column k.at n=48A178618
- a(n) = n*(17*n - 13)/2.at n=33A180232
- List of integers m>0 with m-1 and m+1 both prime, and m-2, m, m+2 all practical.at n=10A209236
- Number of (n+1) X 2 0..3 arrays containing all values 0..3 with every 2 X 2 subblock having three or four distinct values, and new values 0..3 introduced in row major order.at n=3A210176
- Number of (n+1)X5 0..3 arrays containing all values 0..3 with every 2X2 subblock having three or four distinct values, and new values 0..3 introduced in row major order.at n=0A210179