6642
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 20
- Divisor Sum
- 15246
- Proper Divisor Sum (Aliquot Sum)
- 8604
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2160
- Möbius Function
- 0
- Radical
- 246
- Omega Function (Ω)
- 6
- 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
- yes
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 106
- 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
- a(n) = 2*n*(2*n-1).at n=41A002939
- Numbers that are the sum of 2 positive 4th powers.at n=37A003336
- Numbers that are the sum of at most 2 nonzero 4th powers.at n=47A004831
- Number of Twopins positions.at n=19A005687
- Expansion of 1/(1-x^6-x^7-x^8-x^9-x^10-x^11-x^12-x^13-x^14).at n=46A017854
- Powers of fourth root of 15 rounded to nearest integer.at n=13A018088
- Powers of fourth root of 15 rounded up.at n=13A018089
- Fibonacci sequence beginning 1, 17.at n=14A022107
- a(n) = (-1 + prime(n+1)^2)/4.at n=36A024701
- Numbers that are the sum of 3 distinct positive cubes in 2 or more ways.at n=40A024974
- Numbers that are the sum of 3 distinct positive cubes in exactly 2 ways.at n=39A025400
- When squared gives number composed of digits {1,4,6}.at n=16A027677
- Backwards shallow diagonal sums of Catalan triangle A009766.at n=9A030238
- "BIK" (reversible, indistinct, unlabeled) transform of 2,2,2,2...at n=8A032124
- Sums of distinct powers of 9.at n=20A033046
- Positive numbers having the same set of digits in base 2 and base 9.at n=16A037414
- Number of rooted identity trees with 3-colored nodes.at n=5A038079
- Sums of 2 distinct powers of 3.at n=32A038464
- Sums of two distinct powers of 9.at n=8A038487
- Numbers having three 0's in base 9.at n=24A043455