16649
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 16650
- 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
- 16648
- Möbius Function
- -1
- Radical
- 16649
- 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
- 89
- 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
- 1925
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) = 2^(n-1)*(9*n-16) + 9.at n=9A048502
- Primes p that have exactly three primitive roots that are not primitive roots mod p^2.at n=5A060519
- Primes of the form 666*k - 1.at n=8A063472
- 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=[2,6,4]; short d-string notation of pattern = [264].at n=20A078848
- Smallest member of a pair of consecutive twin prime pairs that have three primes between them.at n=21A089635
- Let n range through the odd numbers skipping multiples of 5; a(n) = n-th prime ending in n.at n=19A089779
- Primes which are also prime if their base 64 representation is interpreted as a base 10 number.at n=36A090717
- Primes of the form a^5 + b^3 with a,b>0.at n=21A100273
- Primes p = prime(k) such that both p+2 and prime(k+6)-2 are prime numbers.at n=38A105413
- Numbers n such that p1=2n+3, p2=4n+5, p3=6n+7 and p4=8n+9 are all prime.at n=13A105653
- Primes p such that p + 2 and p*(p + 2) + 2 are primes.at n=32A108013
- Number of permutations of length n which avoid the patterns 3124, 3241, 4321.at n=9A116831
- Prime sums of 6 positive 5th powers.at n=26A123035
- Primes of the form n^2+8.at n=12A138338
- Primes congruent to 11 mod 47.at n=40A142362
- Primes congruent to 7 mod 53.at n=37A142537
- Primes congruent to 11 mod 59.at n=32A142738
- Primes congruent to 57 mod 61.at n=31A142855
- a(n) = 74*n^2 - 1.at n=14A158744
- Primes that can be written as a sum of a positive square and a positive cube in more than one way.at n=34A162930