13009
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 13010
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 13008
- Möbius Function
- -1
- Radical
- 13009
- 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
- 138
- 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
- 1551
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 58 ones.at n=24A031826
- Numerators of continued fraction convergents to sqrt(385).at n=11A041730
- a(1) = 1, a(n) = smallest prime number not already used such that concatenation of a(k) and a(n) is composite for all k = 1 to n-1.at n=41A075612
- Last term of prime quadruples.at n=12A090258
- Primes p such that q-p = 24, where q is the next prime after p.at n=20A098974
- Largest of five consecutive primes the sum of the digits of each of which is prime.at n=33A106717
- Largest prime of the set of five consecutive primes whose sum of digits is a set of five distinct primes.at n=3A106815
- Largest prime of the set of four consecutive primes whose sum of digits is a set of four distinct primes.at n=31A106818
- prime(k) for those k where floor((2*(prime(k+1)-prime(k))*PrimePi(k) mod (8*k))/k) = m with m = 7.at n=30A109561
- Primes of the form k^2 + 13.at n=21A138375
- Primes congruent to 12 mod 41.at n=39A142209
- Primes congruent to 23 mod 43.at n=38A142272
- Primes congruent to 37 mod 47.at n=33A142388
- Primes congruent to 24 mod 49.at n=39A142434
- Primes congruent to 24 mod 53.at n=24A142554
- Primes congruent to 29 mod 59.at n=29A142756
- Primes congruent to 16 mod 61.at n=23A142814
- Primes in A155171.at n=43A155186
- Primes of the form 100*n+9.at n=36A166560
- Primes p containing the string "13" and sum of digits sod(p) = 13.at n=14A175017