6779
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 29
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 6780
- 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
- 6778
- Möbius Function
- -1
- Radical
- 6779
- 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
- 88
- 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
- yes
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 872
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes p == 7, 19, 23 (mod 40) such that (p-1)/2 is also prime.at n=42A000353
- Next prime after n-th Fibonacci number.at n=20A014208
- Primes that are palindromic in base 6.at n=22A029974
- 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=16A031579
- Upper prime of a difference of 16 between consecutive primes.at n=21A031935
- Denominators of continued fraction convergents to sqrt(451).at n=5A041859
- Base-6 palindromes that start with 5.at n=22A043014
- Primes with multiplicative persistence value 5.at n=12A046505
- First of four consecutive primes that comprise two sets of twin primes.at n=29A053778
- Number of polyominoes with n cells, symmetric about two orthogonal axes.at n=30A056877
- Arithmetic mean of largest subset of {A063676(1), ......., A063676(n-1)} such that a(n) is an integer and a(n) is maximal.at n=42A063678
- G.f.: (1 + Sum_{ i >= 0 } 2^i*x^(2^(i+1)-1)) / (1-x)^3.at n=36A063916
- Index values for new maxima in A065925.at n=15A065926
- Twin primes belonging to packs of three or more twin pairs.at n=33A069467
- Primes with either no internal digits or all internal digits are 7.at n=44A069682
- a(0) = 2; a(n) for n > 0 is the smallest prime greater than a(n-1) that differs from a(n-1) by a square.at n=28A073609
- Safe primes (A005385) (p and (p-1)/2 are primes) such that 12*p+1 is also prime.at n=24A075707
- Trajectory of n under the Reverse and Add! operation carried out in base 3 (presumably) does not reach a palindrome and (presumably) does not join the trajectory of any term m < n.at n=21A077405
- Near twin primes of order 12: twin primes p,p+2 such that p+12 and p+14 are primes.at n=29A079292
- Primes arising in A085042: a(n) = the n-th partial sum of A085042.at n=21A085043