9941
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 9942
- 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
- 9940
- Möbius Function
- -1
- Radical
- 9941
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 91
- 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
- 1226
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Mersenne exponents: primes p such that 2^p - 1 is prime. Then 2^p - 1 is called a Mersenne prime.at n=21A000043
- Numbers k such that the continued fraction for sqrt(k) has period 33.at n=27A020372
- Primes of the form j^2 + (j+1)^2.at n=25A027862
- a(n) = floor(47*(n-3/2)^(3/2)).at n=35A050256
- Smallest prime in n-th shell of prime spiral.at n=18A053998
- Number of positive integers <= 2^n of form 5 x^2 + 9 y^2.at n=17A054179
- Primes p whose period of reciprocal equals (p-1)/5.at n=19A056210
- Primes of the form (4*k + 3)^2 + (4*k + 2)^2 where k=0,1,2,3,...at n=7A087872
- Primes p of the form 2*prime(k) + 3 such that 2*prime(k+1) + 3 is the next prime after p.at n=25A089528
- Reverse digits of largest primes, append to sequence if result is larger prime then previous one with reverse digits.at n=18A098922
- Bisection of A000043.at n=10A099983
- Nontrivial Delannoy numbers that are primes.at n=26A101167
- a(n) = 8*n^2 + 4*n + 1.at n=35A102083
- Primes of the form 8*n^2 + 4*n + 1.at n=12A102130
- Berend Jan van der Zwaag's conjectured complete list of numbers that start different "expanding periodic loops" under the mapping described in A053392 and A060630.at n=7A103117
- n-th largest n-digit prime.at n=3A107109
- Numbers whose anti-divisors sum to a prime.at n=45A109350
- Mersenne prime indices that are not Gaussian primes.at n=11A112634
- Reverse digits of largest Chen primes, append to sequence if result is larger Chen prime then previous one with reverse digits.at n=16A118496
- Primes of the form i*prime(i) + (i+1)*prime(i+1).at n=18A119487