7023
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
- 4
- Divisor Sum
- 9368
- Proper Divisor Sum (Aliquot Sum)
- 2345
- 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
- 4680
- Möbius Function
- 1
- Radical
- 7023
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 194
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Decimal part of a(n)^(1/n) starts with a 'nine digits' anagram.at n=38A035136
- Values of n such that 90n+11, 90n+13, 90n+17, 90n+19 are all primes.at n=41A051897
- Numbers k such that 2^k + 21 is prime.at n=30A057201
- McKay-Thompson series of class 44c for Monster.at n=48A058683
- C(n+3)=2*C(n), where C(n) is Cototient(n) := n - phi(n) (A051953).at n=39A063480
- Semiprimes s such that s-/+4 are primes.at n=42A125216
- A bisection of A129095: a(n) = A129095(2n-1) for n>=1.at n=39A129096
- Denominators of an Egyptian fraction for 1/Sqrt[27] = 0.19245...at n=2A145001
- Expansion of x/((1 - x - x^4)*(1 - x)^4).at n=15A145133
- Numbers n with property that A100486(n) is square.at n=47A156913
- Toothpick sequence in the three-dimensional grid.at n=44A160160
- 3 times centered triangular numbers: 9*n*(n+1)/2 + 3.at n=39A164013
- Numbers k such that (k^3 + 2, n^3 + 4) is a twin prime pair.at n=40A178337
- Floor-Sqrt transform of central Stirling numbers of the second kind (A007820).at n=7A192661
- Odd numbers which are factored to the same set of primes in Z as to the irreducible polynomials in GF(2)[X]; odd terms of A235036.at n=15A235039
- Half the number of compositions of n into exactly two different parts with equal multiplicities.at n=21A242911
- Numbers k such that Phi(k, 12) is prime, where Phi is the cyclotomic polynomial.at n=51A252353
- Number of (4+2) X (n+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 3 5 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 3 5 6 or 7.at n=10A252388
- Main diagonal of Unlucky array: a(n) = A255543(n,n).at n=16A255549
- a(n) is (apparently) the largest number k whose Collatz (or '3x+1') trajectory includes the number k + n.at n=31A303876