6923
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 8448
- Proper Divisor Sum (Aliquot Sum)
- 1525
- 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
- 5544
- Möbius Function
- -1
- Radical
- 6923
- 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
- 88
- 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
- Quasi-Carmichael numbers to base 3: squarefree composites n such that prime p|n ==> p-3|n-3.at n=4A029560
- Numbers k such that 45*2^k+1 is prime.at n=19A032372
- Expansion of (1/(1-x^2))*Product_{m>=0} 1/(1-x^(2m+1)).at n=43A038348
- Lower members of a "good pair" of the form (k, 2*k +- 1).at n=43A046861
- Numbers k such that 10^k + 3*R_k is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=10A056698
- Numbers k such that k divides the numerator of B(2k) (the Bernoulli numbers), but gcd(3k, 8^k+1) > 3.at n=13A070192
- a(n) is the smallest k such that number of non-unitary prime divisors of central binomial coefficient, A001405(k) = C(k, floor(k/2)) equals n.at n=18A081394
- a(1) = 1, a(2) = 2, a(3) = 3, a(n+3) = a(n) + a(n+1).at n=30A084338
- Number of positive words of length n in the monoid Br_3 of positive braids on 4 strands.at n=10A097550
- Numbers which are the sum of two positive cubes and divisible by 23.at n=7A101806
- Diagonal sums of Riordan array (1-x-x^2,x(1-x)).at n=34A109266
- Quintuple primorial n##### = n#5.at n=14A114421
- Partial sums of A102540 (primes that are not Chen primes).at n=27A115606
- Antidiagonal sums of triangle A121775.at n=19A121776
- 3-almost primes that are the sum of 2 positive cubes. Sums of 2 positive cubes, with the sums having exactly 3 prime divisors counted with multiplicity.at n=24A122732
- Triangle read by rows, A065941 * A007318.at n=71A153341
- Triangle T(n, k, q) = binomial(n, k) - 1 + q^floor(n/2)*binomial(n-2, k-1) with T(n, 0, q) = T(n, n, q) = 1 and q = 3, read by rows.at n=58A173077
- Triangle T(n, k, q) = binomial(n, k) - 1 + q^floor(n/2)*binomial(n-2, k-1) with T(n, 0, q) = T(n, n, q) = 1 and q = 3, read by rows.at n=62A173077
- Triangle T(n,m), [x*A(x)]^m=sum(n>=m T(n,m)*x^n), where A(x) satisfies x*A(x)^3= -(2*x*A(x)^2+sqrt(1-4*x*A(x)^2)-1)/(4*x*A(x)^2+sqrt(1-4*x*A(x)^2)-1).at n=51A188110
- Numbers n not divisible by 2 or 3 such that k^k == k+1 (mod n) has no nonzero solutions.at n=30A191834