12941
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 12942
- 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
- 12940
- Möbius Function
- -1
- Radical
- 12941
- 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
- 50
- 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
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1541
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of 5-tuples of different integers from [ 1,n ] with no common factors among quadruples.at n=19A015644
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 7.at n=37A031420
- "CGK" (necklace, element, unlabeled) transform of 1,3,5,7,...at n=12A032159
- Numbers k such that sum of the first k primes is a palindrome.at n=5A038582
- a(n) = Sum_{i=0..2n} (-1)^i * T(i,2n-i), array T as in A049735.at n=32A049737
- Prime number spiral (clockwise, North spoke).at n=20A054551
- A list of equal temperaments (equal divisions of the octave) whose nearest scale steps are closer and closer approximations to the ratios of two tones of musical harmony: the perfect 4th, 4/3 and its complement the perfect 5th, 3/2.at n=21A060528
- a(1)=1, a(n) is the smallest integer > a(n-1) such that the largest element in the simple continued fraction for S(n)=1/a(1)+1/a(2)+...+1/a(n) equals n^2.at n=18A070902
- Primes which are sandwiched between two numbers having the same unordered canonical form.at n=37A074460
- A014486-indices of A083932-trees.at n=28A083934
- Primes such that a sum of any two adjacent digits is prime; first and last digits are considered adjacent.at n=37A086244
- Mountain primes.at n=34A134951
- Nonzero entries in the array on page 8 of the reference.at n=37A140878
- Primes congruent to 28 mod 37.at n=36A142137
- Primes congruent to 26 mod 41.at n=42A142223
- Primes congruent to 41 mod 43.at n=31A142290
- Primes congruent to 16 mod 47.at n=33A142367
- Primes congruent to 9 mod 53.at n=32A142539
- Primes congruent to 16 mod 55.at n=39A142612
- Primes congruent to 20 mod 59.at n=26A142747