6045
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 10752
- Proper Divisor Sum (Aliquot Sum)
- 4707
- 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
- 2880
- Möbius Function
- 1
- Radical
- 6045
- 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
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 93
- 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
- a(1)=0; for n>1, a(n) = number of isomeric hydrocarbons of the acetylene series with carbon content n.at n=13A000642
- Pseudoprimes to base 92.at n=42A020220
- Every run of digits of n in base 14 has length 2.at n=36A033012
- a(n) = n*(4*n-1).at n=39A033991
- Record values of sigma(n).at n=51A034885
- Number of partitions of n into parts not of form 4k+2, 24k, 24k+9 or 24k-9. Also number of partitions in which no odd part is repeated, with at most 4 parts of size less than or equal to 2 and where differences between parts at distance 5 are greater than 1 when the smallest part is odd and greater than 2 when the smallest part is even.at n=44A036033
- Positive integers having more base-14 runs of even length than odd.at n=38A044840
- Squarefree odd numbers with exactly 4 distinct prime factors.at n=31A046390
- Peak values reached by A062402 at the sites listed in A065389.at n=47A065390
- Sum of divisors of twice square numbers.at n=29A065765
- The numbers D in the set {D :=(2n+1)^2-4m^2, 1<=m<=n} that generate the smallest solution x to x^2 - D*y^2 = 1.at n=38A074074
- The numbers D in the set {D :=(2n+1)^2-4m^2, 1<=m<=n} that generate the smallest solution x to x^2 - D*y^2 = 1.at n=47A074074
- 2-apexes of omega: numbers k such that omega(k-2) < omega(k-1) < omega(k) > omega(k+1) > omega(k+2), where omega(m) = the number of distinct prime factors of m.at n=31A076762
- 2-nadirs of phi: numbers k such that phi(k-2) > phi(k-1) > phi(k) < phi(k+1) < phi(k+2).at n=28A076773
- Odd squarefree numbers k such that k/phi(k) > 2, where phi is Euler's totient function.at n=33A091495
- Numbers, not divisible by 10, whose digits can be permuted to get a proper divisor.at n=26A096093
- Consider iteration of the function f(x) = sigma(phi(x)) = A062402(x). Sequence lists the numbers k such that the trajectory of k returns to k.at n=26A096998
- A062402(x)=sigma(phi[x]) function is iterated; initial value=2^n; a(n)=smallest term of trajectory.at n=13A097002
- Sum of the primes in ordered 3 X 3 prime squares.at n=13A105089
- Expansion of (1+t^3)^2/((1-t)*(1-t^2)^2*(1-t^4)).at n=51A106607