16641
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 9
- Divisor Sum
- 24609
- Proper Divisor Sum (Aliquot Sum)
- 7968
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10836
- Möbius Function
- 0
- Radical
- 129
- Omega Function (Ω)
- 4
- 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
- yes
- 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
- 53
- 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
- yes
- Achilles Number
- no
- Perfect Power
- yes
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Centered 4-dimensional orthoplex numbers (crystal ball sequence for 4-dimensional cubic lattice).at n=12A001846
- Numbers that are the sum of 4 positive 7th powers.at n=17A003371
- Numbers that are the sum of at most 4 positive 7th powers.at n=43A004866
- Partial quotients in continued fraction expansion of Cahen's constant.at n=7A006280
- Squares formed by concatenating other squares, not ending in 0.at n=22A009404
- a(n) = (3*n)^2.at n=43A016766
- a(n) = (4*n + 1)^2.at n=32A016814
- a(n) = (5*n + 4)^2.at n=25A016898
- a(n) = (6*n+3)^2.at n=21A016946
- a(n) = (7*n + 3)^2.at n=18A017018
- a(n) = (8*n + 1)^2.at n=16A017078
- a(n) = (9*n + 3)^2.at n=14A017198
- a(n) = (10*n + 9)^2.at n=12A017378
- a(n) = (11*n + 8)^2.at n=11A017486
- a(n) = (12*n + 9)^2.at n=10A017630
- Squares which are a decimal concatenation of two or more squares.at n=34A019547
- a(n) = T(3n,n), where T = Delannoy triangle (A008288).at n=4A026001
- Squares composed of digits {1,4,6}.at n=10A027676
- a(n) = (2^n + 1)^2.at n=7A028400
- Denominator of x-coordinate of (2n)*P where P = (0,0) is the generator for rational points on the curve y^2 + y = x^3 - x.at n=6A028937