6069
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 9824
- Proper Divisor Sum (Aliquot Sum)
- 3755
- 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
- 3264
- Möbius Function
- 0
- Radical
- 357
- Omega Function (Ω)
- 4
- 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
- 62
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- 9-gonal (or enneagonal or nonagonal) numbers: a(n) = n*(7*n-5)/2.at n=42A001106
- a(n) = ceiling((1 + sum of preceding terms) / 2) starting with a(0) = 1.at n=22A005428
- Pisot sequence E(4,25): a(n) = floor(a(n-1)^2/a(n-2)+1/2) for n>1, a(0)=4, a(1)=25.at n=4A010909
- Pisot sequence E(10,18), a(n)=[ a(n-1)^2/a(n-2)+1/2 ].at n=11A014006
- a(n) = (2*n - 13)*n^2.at n=17A015246
- Number of monotone Boolean functions of n variables with 2 mincuts. Also number of Sperner systems with 2 blocks.at n=5A016269
- Odd 9-gonal (or enneagonal) numbers.at n=21A028991
- a() = 1,3,... [ A037257 ], differences = 2,... [ A037258 ] and 2nd differences [ A037259 ] are disjoint and monotonic; adjoin next free number to 2nd differences unless it would produce a duplicate in which case ignore.at n=28A037257
- Matrix 5th power of partition triangle A008284.at n=57A039807
- Iterated procedure 'composite k added to sum of its prime factors reaches a prime' yields 5 skipped primes.at n=45A050772
- Numbers k such that k | sigma_8(k).at n=12A055712
- Integer part of log(n)^(sqrt(n)*log(n)).at n=12A062423
- a(n) = (9*n^2 + 13*n + 6)/2.at n=36A064226
- a(n) = 21*n^2.at n=17A064762
- Half the number of n X 7 binary arrays with a path of adjacent 1's and a path of adjacent 0's from top row to bottom row.at n=1A069407
- Numbers n such that sum of digits of n equals the squarefree part of n.at n=40A070274
- a(1)=1, a(n) is the smallest integer > a(n-1) such that the sum of elements of the simple continued fraction for S(n)=1/a(1)+1/a(2)+...+1/a(n) equals n^4.at n=3A071972
- a(n) = ceiling((Sum_{k=1..n-1} a(k)) / 2) for n >= 2 starting with a(1) = 1.at n=23A073941
- Subsequence of A005428 where state = 2.at n=11A081615
- Numbers k such that k#*2^k-1 is prime, where k# = product of primes <= k.at n=49A084406