12321
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 9
- Divisor Sum
- 18291
- Proper Divisor Sum (Aliquot Sum)
- 5970
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7992
- Möbius Function
- 0
- Radical
- 111
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 156
- 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
- Squares written in base 4.at n=21A001739
- Squares written in base 5.at n=31A001740
- Squares written in base 6.at n=43A001741
- Wonderful Demlo numbers: a(n) = ((10^n - 1)/9)^2.at n=2A002477
- Palindromic squares.at n=8A002779
- Concatenation of sequence (1, 2, ..., floor((n-1)/2), floor(n/2), floor(n/2)-1, ..., 1) for n >= 1.at n=4A007907
- Squares of palindromes.at n=20A014186
- Numbers k that divide s(k), where s(1)=1, s(j)=9*s(j-1)+j.at n=41A014857
- Numbers k such that k divides s(k), where s(1)=1, s(j)= s(j-1) + j*7^(j-1).at n=25A014948
- Numbers m such that m divides 10^m - 1.at n=15A014950
- Numbers k such that k | 11^k + 1.at n=19A015960
- a(n) = (3*n)^2.at n=37A016766
- a(n) = (4n + 3)^2.at n=27A016838
- a(n) = (5*n + 1)^2.at n=22A016862
- a(n) = (6*n+3)^2.at n=18A016946
- a(n) = (7*n + 6)^2.at n=15A017054
- a(n) = (8*n + 7)^2.at n=13A017150
- a(n) = (9*n + 3)^2.at n=12A017198
- a(n) = (10*n + 1)^2.at n=11A017282
- a(n) = (11*n+1)^2.at n=10A017402