6679
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 6680
- 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
- 6678
- Möbius Function
- -1
- Radical
- 6679
- 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
- 93
- 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
- 861
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Exponentiation of g.f. for Fibonacci numbers.at n=8A006701
- a(n) = prime(n*(n+1)/2).at n=40A011756
- Values of k at which the period of the continued fraction for sqrt(k) sets a new record.at n=43A013645
- Primes that remain prime through 2 iterations of the function f(x) = 5x + 8.at n=46A023255
- Primes that remain prime through 3 iterations of function f(x) = 5x + 8.at n=16A023286
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 81.at n=10A031579
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 74 ones.at n=1A031842
- Numbers whose base-9 representation has exactly 5 runs.at n=25A043634
- Primes whose sum of digits is the perfect number 28.at n=8A048517
- Primes or negative values of primes in the sequence b(n) = 47*n^2 - 1701*n + 10181, n >= 0.at n=34A050267
- Primes followed by a [10,2,10] prime difference pattern of A001223.at n=11A052376
- Birthday set of order 9: i.e., numbers congruent to +- 1 modulo 2, 3, 4, 5, 6, 7, 8 and 9.at n=42A057541
- Primes p such that p and p^2 have same digit sum.at n=15A058370
- Primes p such that x^53 = 2 has no solution mod p.at n=14A059258
- Primes p such that x^18 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.at n=16A059664
- Primes p such that x^54 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.at n=17A059665
- Primes p such that x^36 = 2 has no solution mod p, but x^12 = 2 has a solution mod p.at n=11A059668
- Primes p such that p^5 reversed is also prime.at n=42A059698
- Primes p such that p^10 reversed is also prime.at n=32A059703
- Odd prime values of sigma(k) - phi(k) taking k in increasing order.at n=28A068419