7185
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 11520
- Proper Divisor Sum (Aliquot Sum)
- 4335
- 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
- 3824
- Möbius Function
- -1
- Radical
- 7185
- Omega Function (Ω)
- 3
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 70
- 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
- no
- Odd
- yes
Appears in sequences
- arctan(sin(x)-tan(x))=-3/3!*x^3-15/5!*x^5-273/7!*x^7+7185/9!*x^9...at n=3A013354
- a(n) = position of 3*n^3 in A003072.at n=27A024970
- Integer part of log(n)^(n^(1 - 1/n)).at n=11A062465
- Nearest integer to log(n)^(n^(1 - 1/n)).at n=11A062466
- Numbers n for which there are exactly five k such that n = k + (product of nonzero digits of k).at n=17A096926
- a(n) = 9^n + 5^n - 1.at n=4A155636
- Numbers of the form p*q*r, where p < q < r are odd primes such that r = +/-1 (mod p*q).at n=41A160353
- Magnetic Tower of Hanoi, total number of moves, optimally solving the [RED ; NEUTRAL ; BLUE] pre-colored puzzle.at n=9A183114
- Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,2,1,0,1 for x=0,1,2,3,4.at n=3A197799
- Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,2,1,0,1 for x=0,1,2,3,4.at n=3A197801
- T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,2,1,0,1 for x=0,1,2,3,4.at n=24A197805
- Number of (w,x,y,z) with all terms in {1,...,n} and 3w=x+y+z+n+2.at n=30A212252
- Ordered counts of internal lattice points within primitive Pythagorean triangles (PPT).at n=38A225414
- Numbers k such that sigma(tau(phi(k))) = phi(tau(sigma(k))).at n=31A226118
- Numbers of espalier polycubes of a given volume in dimension 4.at n=21A229917
- Number of partitions p of n such that if h = 2*min(p), then h is an (h,0)-separator of p; see Comments.at n=54A239511
- Number of compositions of n such that the smallest part has multiplicity two.at n=15A241862
- Binary representation of base-(i-1) expansion of -n: replace i-1 with 2 in base-(i-1) expansion of -n.at n=35A256441
- Number of nX7 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.at n=5A266934
- T(n,k)=Number of nXk binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.at n=71A266935