6389
domain: N
Properties
Digital Properties
- Digit Count
- 4
- 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
- 6390
- 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
- 6388
- Möbius Function
- -1
- Radical
- 6389
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 124
- 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
- 833
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of functional digraphs (digraphs of functions on n nodes where every node has outdegree 1 and loops of length 1 are forbidden).at n=11A001373
- Numbers k such that (6^k - 1)/5 is prime.at n=9A004062
- Incorrect duplicate of A297408.at n=6A007355
- Numbers k such that the continued fraction for sqrt(k) has period 67.at n=6A020406
- Numbers having period-4 6-digitized sequences.at n=35A031197
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 32 ones.at n=39A031800
- a(n) = Sum_{i=0..floor(n/2)} T(2i,n-2i) where T is A049627.at n=49A049630
- a(n) = Sum_{i=0..floor(n/2)} T(2i+1,n-2i-1) where T is A049627.at n=49A049631
- Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 19.at n=19A050968
- Geometric mean of the digits = 6. In other words, the product of the digits is = 6^k where k is the number of digits.at n=32A061429
- Numbers k such that [A070080(k), A070081(k), A070082(k)] is an obtuse integer triangle with integer area.at n=31A070147
- Primes of the form x^2 + (x+3)^2.at n=15A076727
- Prime numbers using only the curved digits 0, 3, 6, 8 and 9.at n=20A079652
- a(n) is the smallest prime == 1 (mod F(n)) where F(n) is the n-th Fibonacci number.at n=16A087384
- Primes of the form n^2 - 11.at n=14A091272
- Smallest prime with digit product 6^n.at n=4A091465
- Smallest prime p such that the maximum run length of consecutive positive quadratic residues modulo p is n.at n=18A097159
- a(n) = least odd prime p such that (p^(P(n))-1)/(p-1) is prime with P(i) = i-th prime, n>1.at n=48A101636
- Numbers k such that 7*10^k - 9 is prime.at n=21A103048
- Primes from merging of 4 successive digits in decimal expansion of Zeta(2) or (Pi^2)/6.at n=36A105377