9420
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
- 24
- Divisor Sum
- 26544
- Proper Divisor Sum (Aliquot Sum)
- 17124
- 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
- 2496
- Möbius Function
- 0
- Radical
- 4710
- Omega Function (Ω)
- 5
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 34
- 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(2n) (the number of true cycles of length 2n in which a certain node is included) for zeolite CLO = Cloverite starting with a T5 atom.at n=6A018999
- Triangle of coefficients, read by rows, where T(n,k) is the coefficient of x^n*y^k in f(x,y) that satisfies f(x,y) = (3-sqrt(1-4x))/2 + xy*f(x,y)^3.at n=47A086636
- Triangle, read by rows, of trinomial coefficients arranged so that there are n+1 terms in row n by setting T(n,k) equal to the coefficient of z^k in (2 + 3*z + z^2)^(n-[k/2]), for n>=k>=0, where [k/2] is the integer floor of k/2.at n=40A099527
- Maximum number of different determinants that can be produced by permuting the elements of a 3 X 3 integer matrix with nonnegative entries <= n.at n=33A099834
- Sum of CarmichaelLambda[n] between successive powers of 2.at n=7A104196
- Positive integers n such that n^11 + 1 is semiprime.at n=41A105122
- a(1) = 932; for n > 1, a(n) = a(n-1) + 1 + sum of distinct prime factors of a(n-1) that are < a(n-1).at n=25A105213
- Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1),U=(1,2), or d=(1,-1) and have k peaks (i.e., ud and Ud's).at n=19A108425
- Positive integers i for which A112049(i) == 7.at n=21A112067
- Next term is the sum of previous term and the square of the sum of its decimal digits, with a(0) = 10.at n=30A112787
- Numbers k such that k^2 divides 13^k - 1.at n=47A128393
- Averages of twin prime pairs that are sums of 5 consecutive averages of twin prime pairs.at n=7A160919
- G.f. satisfies: A(x) = A(x^2)^2 + x*A(x^2)^3.at n=32A174512
- A 2n X 2n square filled with "ON" cells becomes a period a(n) oscillator using the life-like cellular automaton B345/S4567.at n=12A178699
- The Wiener index of the Dutch windmill graph D(5,n) (n>=1).at n=19A180579
- Triangle, read by rows of 2*n+1 terms, where row n lists the coefficients in (1+3*x+2*x^2)^n.at n=44A200536
- Row sums of triangle A178473.at n=4A203509
- Number of partitions p of n such that the multiplicity of (max(p) - min(p)) is a part.at n=43A240495
- Number of tilings of a 5 X n rectangle using n pentominoes of shapes F, U, X, N.at n=23A247126
- Numbers n such that n is both the average of some twin prime pair p, q (q = p+2) (i.e., n = p+1 = q-1) and is also the arithmetic mean of the four numbers consisting of the two primes before p and the two primes after q.at n=22A256620