16979
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 32
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 16980
- 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
- 16978
- Möbius Function
- -1
- Radical
- 16979
- 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
- 66
- 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
- 1957
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Smallest prime p==3 (mod 8) such that Q(sqrt(-p)) has class number 2n+1.at n=31A002148
- Primes that remain prime through 3 iterations of function f(x) = 9x + 8.at n=39A023298
- Primes that remain prime through 4 iterations of function f(x) = 6x + 5.at n=21A023317
- Primes that remain prime through 5 iterations of function f(x) = 6x + 5.at n=5A023345
- Denominators of continued fraction convergents to sqrt(655).at n=8A042259
- Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <=6 (i.e., when d=2,4 or 6) and forming d-pattern=[2, 6,6]; short d-string notation of pattern = [266].at n=8A078849
- Primes with digit sum = 32.at n=6A106768
- Primes congruent to 46 mod 59.at n=29A142773
- Primes congruent to 21 mod 61.at n=32A142819
- Primes p such that (p reversed)+ 8 is a square.at n=38A167470
- Number of n X 2 0..3 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.at n=35A201975
- Last occurrence of n partitions in A205617.at n=39A205618
- Lesser of twin primes (A001359) such that both are full reptend primes (A001913).at n=40A243096
- Primes p such that p^10 - p^9 - p^8 - p^7 - p^6 - p^5 - p^4 - p^3 - p^2 - p - 1 is prime.at n=40A243402
- Primes (with d digits, say) that generate another prime when acted on by the "standard" superpermutation of length A007489(d) of d elements (cf. comment).at n=30A244311
- Lesser of twin prime pairs of the form (40n - 21, 40n - 19).at n=25A250025
- Non-palindromic balanced primes in base 16.at n=16A256090
- a(n) = Sum_{k=0..n+1}(binomial(n-1,k)/(k+1)*binomial(n+k+1,n-k)).at n=8A262441
- Primes p such that p+2^3, p+2^5 and p+2^7 are all primes.at n=28A275475
- Lesser of the pairs of twin primes in A001122.at n=40A319248