6566
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 11628
- Proper Divisor Sum (Aliquot Sum)
- 5062
- 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
- 2772
- Möbius Function
- 0
- Radical
- 938
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 75
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers that are the sum of 8 positive 7th powers.at n=24A003375
- Numbers that are the sum of 6 nonzero 8th powers.at n=7A003384
- Numbers that are the sum of at most 6 nonzero 8th powers.at n=33A004879
- Numbers that are the sum of at most 7 nonzero 8th powers.at n=41A004880
- Numbers that are the sum of at most 8 nonzero 8th powers.at n=50A004881
- a(n) = n^2*(5*n-3)/2.at n=14A006597
- If a, b in sequence, so is ab+10.at n=32A009368
- a(n) = n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2.at n=39A027575
- Pair up the numbers.at n=32A030655
- Numbers having three 0's in base 9.at n=12A043455
- Numbers having three 6's in base 10.at n=11A043515
- Numbers whose base-4 representation contains exactly three 1's and four 2's.at n=7A045104
- McKay-Thompson series of class 35B for Monster.at n=37A058641
- a(2n) = concatenation of 4n+1 and 4n+2, a(2n+1) = concatenation of the two most nearly equal numbers whose product is a(2n).at n=32A068517
- If D[n] is divisor-set of n, then in set of 1+D only 2 primes occur:{2,3}; also n is not squarefree.at n=20A072607
- Partition the concatenation 1234567...of natural numbers into successive strings nontrivially (a(n) is not equal to n) such that the n-th string is a multiple of n.at n=13A077293
- Partition the concatenation 1234567...of natural numbers into successive strings which are multiples of 7, all different and > 7 (0 is never taken as the most significant digit).at n=15A077300
- Nontrivial slowest increasing sequence whose succession of digits is that of the nonnegative integers.at n=33A098080
- a(1)=1, a(2)=2. a(n) is the a(n-1)th integer from among those positive integers coprime to a(n-2).at n=23A126881
- Partial sum of centered tetrahedral numbers A005894.at n=13A132366