4605
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
- 8
- Divisor Sum
- 7392
- Proper Divisor Sum (Aliquot Sum)
- 2787
- 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
- 2448
- Möbius Function
- -1
- Radical
- 4605
- 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
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 59
- 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
- Numbers whose base-7 representation contains exactly three 6's.at n=32A043419
- Numbers whose base-4 representation contains exactly three 1's and three 3's.at n=23A045127
- Sum of divisors of twice square numbers.at n=33A065765
- a(1)=1, a(n) is the smallest integer > a(n-1) such that the largest element in the simple continued fraction for S(n)=1/a(1)+1/a(2)+...+1/a(n) equals 3n.at n=31A070899
- Partial sums of usigma(n)^2: square of the sum of unitary divisors of n.at n=18A074789
- Let u(1)=u(2)=1, u(3)=n, u(k) = (1/2)*abs(2*u(k-1) -u(k-2)-u(k-3)); sequence gives values of n such that Sum_{k>=1} u(k) is an integer.at n=19A078113
- a(n) = Sum_{i=1..n} LookAndSay(i).at n=13A079664
- Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=3, r=3, I={0,2}.at n=13A079993
- Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=3, r=3, I={2}.at n=10A079995
- Where records occur in numerators of Kepler's tree of harmonic fractions (A093873).at n=47A095725
- Numbers k such that k^4 + 4 is semiprime.at n=42A108814
- a(n) = 8*n^2 - 3.at n=23A108928
- a(1)=3; a(n)=floor((20+sum(a(1) to a(n-1)))/6).at n=48A120180
- Number of complete partitions of n.at n=31A126796
- a(n+1)-+a(n)=prime, a(n+1)*a(n)=Average of twin prime pairs, a(1)=2,a(2)=9.at n=23A154495
- (n^3 - n + 15)/3.at n=23A155757
- Numbers k such that k^2 == 2 (mod 23^2).at n=17A156849
- a(n) = ((2^b-1)/phi(n))*Sum_{d|n} Moebius(n/d)*d^(b-1) for b = 4.at n=16A160892
- Row sums of triangle defined in A112593.at n=44A160991
- a(n) is the smallest positive number B that yields a solution for k = A167219(n).at n=29A167221