4639
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 4640
- 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
- 4638
- Möbius Function
- -1
- Radical
- 4639
- 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
- 90
- 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
- 626
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of different score sequences that are possible in an n-team round-robin tournament.at n=11A000571
- Number of polygonal graphs.at n=26A002560
- Coordination sequence T2 for Zeolite Code DAC.at n=43A008068
- Coordination sequence T2 for Zeolite Code DOH.at n=42A008079
- Coordination sequence T1 for Zeolite Code YUG.at n=44A008247
- A B_2 sequence: a(n) = least value such that the sequence increases and pairwise sums of distinct terms are all distinct.at n=50A010672
- Odd primes such that (3p+1)/2 and 3p+4 are also prime.at n=35A014223
- Numbers k such that the continued fraction for sqrt(k) has period 84.at n=8A020423
- Primes that remain prime through 2 iterations of function f(x) = 5x + 2.at n=46A023252
- Primes that remain prime through 2 iterations of the function f(x) = 8*x + 5.at n=36A023262
- Numbers k such that k^2 is palindromic in base 15.at n=39A030073
- 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 67.at n=13A031565
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 30 ones.at n=33A031798
- Coordination sequence T3 for Zeolite Code CFI.at n=45A033601
- Coordination sequence T16 for Zeolite Code STT.at n=45A038425
- Primes p such that both p-2 and 2p-1 are prime.at n=31A038869
- Primes p such that p+4 and p+12 are also prime.at n=34A046137
- Euclid-Mullin sequence (A000945) with initial value a(1)=17 instead of a(1)=2.at n=15A051311
- Smallest prime in n-th shell of prime spiral.at n=13A053998
- Primes q of form q = 10p + 9, where p is also prime.at n=43A055784