9210
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 22176
- Proper Divisor Sum (Aliquot Sum)
- 12966
- 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
- 2448
- Möbius Function
- 1
- Radical
- 9210
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 60
- 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
- Expansion of Product_{m >= 1} (1-m*q^m)^10.at n=11A022670
- Expansion of 1/((1-3x)(1-7x)(1-9x)(1-11x)).at n=3A028094
- Numerators of continued fraction convergents to sqrt(349).at n=6A041660
- Expansion of 1/(1-2*x-3*x^2+2*x^3).at n=9A046672
- Start with a single triangle; at n-th generation add a triangle at each vertex, allowing triangles to overlap; sequence gives number of triangles in n-th generation.at n=21A061776
- a(1)=1, a(n)=ceiling(n/(n+1)*sum(k=1,n-1,a(k))).at n=15A082423
- a(n) = 9*2^n - 6.at n=10A089143
- Let p(n) be the n-th prime congruent to 1 mod 4. Then a(n) = the least m for which m^2+1=p(n)*k^2 has a solution.at n=32A094048
- 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=30A099834
- Slowest increasing sequence where the absolute difference between the last digit of a(n) and the first digit of a(n+1) equals 9.at n=33A101243
- Bond series for first perpendicular moment of 4.8 (bathroom tile) lattice.at n=18A120556
- a(n) = 256*n^2 - n.at n=5A158010
- a(n) = 1024*n^2 - 2*n.at n=2A158420
- a(n) = 36*n^2 - 6.at n=15A158462
- a(n) = (2*n^3 + 5*n^2 + 21*n)/2.at n=19A162266
- For each permutation of {1,2,...,n} one or more integers might not be part of any longest increasing subsequence (LIS) of that permutation. The sequence lists the number of permutations for which ceiling(n/2) is not part of any LIS. For example, if n=4, 2 is not in any LIS of the two permutations (1342) and (3421).at n=7A168502
- Numbers n for which n' + n and n' - n are both prime, n' being the arithmetic derivative of n.at n=25A229272
- Number of 2 X n 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4.at n=35A240001
- Numbers k such that 4^k + 33 is prime.at n=18A262972
- Indices where records occur in A265432.at n=33A272675