2309
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2310
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 2308
- Möbius Function
- -1
- Radical
- 2309
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 32
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 343
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of permutations of [n] in which the longest increasing run has length 3.at n=6A000402
- Largest prime factor of product of first n primes - 1, or 1 if no such prime exists.at n=4A002584
- Smallest number that requires n iterations of the bi-unitary totient function (A116550) to reach 1.at n=32A005424
- Largest prime <= Product prime(k).at n=4A007014
- Smallest prime > n^2.at n=47A007491
- Coordination sequence T1 for Zeolite Code EAB.at n=35A008082
- Triangle read by rows: T(n,k) (n>=1; 1<=k<=n) is the number of permutations of [n] in which the longest increasing run has length k.at n=23A008304
- Coordination sequence T6 for Zeolite Code TER.at n=32A016438
- Megaperfect numbers: numbers n where A019294(n) = min {m: n divides sigma^(m) (n)} increases to a record; sigma^(m) means apply the sum-of-divisors function m times.at n=24A019276
- Numbers k such that the continued fraction for sqrt(k) has period 19.at n=18A020358
- a(n) = [ a(n-1)/a(1) + a(n-2)/a(2) + ... + a(1)/a(n-1) ], for n >= 3.at n=19A022875
- Primes that remain prime through 2 iterations of function f(x) = 10x + 9.at n=42A023270
- Primes that remain prime through 3 iterations of function f(x) = 10x + 9.at n=13A023301
- Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 18 (most significant digit on right).at n=18A029511
- Primes in which parity of digits alternates.at n=54A030144
- Product of first n palindromic primes minus 1.at n=4A030522
- a(n) = prime(8*n - 1).at n=42A031374
- a(n) = prime(10*n-7).at n=34A031917
- a(n) = prime(9*n-8).at n=38A031918
- Upper prime of a difference of 12 between consecutive primes.at n=21A031931