13431
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 20216
- Proper Divisor Sum (Aliquot Sum)
- 6785
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7920
- Möbius Function
- 0
- Radical
- 1221
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 138
- 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
- Palindromic Super-2 Numbers.at n=20A032750
- Numbers that are palindromic, divisible by 11 and have an odd number of digits.at n=11A045571
- Catafusenes (see reference for precise definition).at n=10A045905
- Palindromes with exactly 4 prime factors (counted with multiplicity).at n=42A046330
- a(n) = smallest palindrome > a(n-1) such that a(1)*a(2)*...*a(n) + 1 is prime with a(1) = 2.at n=19A051896
- Numbers k such that reverse(gpf(k)) = gpf(k+1), where gpf(n) = A006530(n); a(1)=1.at n=23A071844
- Numbers n for which there are exactly four k such that n = k + reverse(k).at n=30A072428
- Palindromic time display in hours, minutes, seconds on a six spaced 24-hour digital clock, using hours 1-24.at n=34A082567
- Beginning with 2, smallest palindrome >= the previous term such that every concatenation is a prime.at n=13A088093
- Number of compositions (ordered partitions) of n into n parts, allowing zeros, with distinct nonzero parts.at n=10A097965
- Palindromes n such that 10n01 is a prime.at n=21A099744
- a(1) = 1, then the rearrangement of odd palindromes such that every concatenation is a prime for n > 1.at n=44A113578
- Four-column table read by rows: number of nonisomorphic systems of catafusenes in an example (see Cyvin et al. (1994) for precise definition).at n=39A121178
- Sequence representing valid nontrivial 1-dimensional Hashi (a.k.a. Bridges or Hashiwokakero) puzzle orientations.at n=36A143964
- Sum of digits of square is sum of square of digits.at n=41A165550
- Partial sums of near-repdigit primes A056710.at n=26A172983
- Palindromic mountain numbers.at n=16A173070
- Number of (n+2)X(6+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=24A254905
- Palindromic numbers such that the sum of the digits equals the number of divisors.at n=15A263720
- Numbers k such that (5 * 10^k - 119)/3 is prime.at n=27A271109