6009
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
- 4
- Divisor Sum
- 8016
- Proper Divisor Sum (Aliquot Sum)
- 2007
- 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
- 4004
- Möbius Function
- 1
- Radical
- 6009
- 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
- 93
- 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
- Strobogrammatic numbers: the same upside down.at n=24A000787
- sec(cos(x)*sin(x))=1+1/2!*x^2-11/4!*x^4-83/6!*x^6+10505/8!*x^8...at n=5A012478
- Numbers k such that the continued fraction for sqrt(k) has period 96.at n=9A020435
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 50.at n=38A031548
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 50 ones.at n=11A031818
- Number of partitions satisfying cn(2,5) + cn(3,5) <= cn(0,5).at n=39A039861
- Numbers n such that 91*2^n-1 is prime.at n=22A050571
- Numbers that are unchanged when turned upside down, when written in a font in which 7 looks like upside-down 2.at n=41A051791
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 61 ).at n=39A063334
- Index of smallest Fibonacci number beginning with the n-th Fibonacci number other than itself.at n=22A072520
- Sum of remainders when n-th Fibonacci number is divided by all smaller Fibonacci numbers > 1.at n=19A072523
- Numbers that look the same when rotated by 180 degrees, using only digits 0, 6 and 9.at n=5A111065
- Numbers that look the same when printed upside down.at n=11A111156
- a(n) = floor(n*(n+2)*(n+4)*(n-6)/192).at n=33A117652
- Semiprimes that are semiprimes turned upside-down.at n=31A119738
- Numbers n such that n^3 is zeroless pandigital.at n=22A124628
- Semiprimes s such that s-/+2 are primes.at n=35A125215
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, 1), (0, 1, -1), (1, 0, -1), (1, 1, 0)}.at n=8A148951
- Number of walks within N^2 (the first quadrant of Z^2) starting and ending at (0,0) and consisting of n steps taken from {(-1, 0), (-1, 1), (0, -1), (1, 0)}.at n=12A151346
- a(n) = n^3 + sum((-1)^j*a(j)); for j=1 to n-1; a(1)=1.at n=26A153286