9207
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 15360
- Proper Divisor Sum (Aliquot Sum)
- 6153
- 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
- 5400
- Möbius Function
- 0
- Radical
- 1023
- Omega Function (Ω)
- 5
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 122
- 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
- no
- Odd
- yes
Appears in sequences
- Number of up/down (initially ascending) compositions of n.at n=22A025048
- a(n) = Sum_{k=0..n} (k+1) * A026703(n, k).at n=9A027256
- Multiplicity of highest weight (or singular) vectors associated with character chi_151 of Monster module.at n=38A034539
- Number of nondividing sets on {1,2,...,n}.at n=34A051014
- a(n) = (11*n+5)*(n+4)*(n+3)*(n+2)*(n+1)/120.at n=8A056118
- Sum of binary numbers with n 1's and one (possibly leading) 0.at n=9A059672
- Array defined in A064643 read from left to right (cf. A107783).at n=34A064644
- Numbers n such that [A070080(n), A070081(n), A070082(n)] is an isosceles integer triangle with integer area.at n=25A070145
- Numbers n such that [A070080(n), A070081(n), A070082(n)] is an acute integer triangle with integer area.at n=25A070146
- a(1)=1, a(n)=2*a(n-1)+1 if that number is not squarefree, a(n)=a(n-1)+1 otherwise.at n=52A081870
- Numbers n divisible by exactly two nontrivial permutations (rearrangements) of the digits of n.at n=7A090057
- Numbers which are the sum of two positive cubes and divisible by 11.at n=16A101852
- Numbers which are the sum of two positive cubes and divisible by 31.at n=15A102658
- Array defined in A064643 read in direction in which it was created.at n=29A107783
- Numbers k such that k and k+5 are 5-almost primes.at n=35A124942
- Numbers k such that A127483(k) = A127483(k+1) - 1 = A127483(k+2) - 2.at n=31A127485
- a(n) = (n^5 + 145*n^4 + 905*n^3 + 155*n^2 + 594*n + 120)/120.at n=8A143060
- First trisection of A028560.at n=31A147651
- First of two consecutive numbers with at least one 3 in their prime signature.at n=45A176313
- Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+217)^2 = y^2.at n=22A198294