4219
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 4220
- 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
- 4218
- Möbius Function
- -1
- Radical
- 4219
- 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
- 157
- 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
- 578
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Cuban primes: primes which are the difference of two consecutive cubes.at n=19A002407
- Hex (or centered hexagonal) numbers: 3*n*(n+1)+1 (crystal ball sequence for hexagonal lattice).at n=37A003215
- Expansion of (1+x^2)(1+x^4)/((1-x)^2*(1-x^2)*(1-x^3)).at n=33A007979
- Primes that divide at least one term of Sylvester's sequence s = A000058: s(n+1) = s(n)^2 - s(n) + 1, s(0) = 2.at n=18A007996
- Coordination sequence for FeS2-Pyrite, S position.at n=30A009956
- Number of ordered quadruples of integers from [ 2,n ] with no global factor.at n=16A015638
- Numbers k such that the continued fraction for sqrt(k) has period 74.at n=8A020413
- a(n) = least m such that if r and s in {1/3, 1/6, 1/9,..., 1/3n} satisfy r < s, then r < k/m < s for some integer k.at n=42A024824
- a(n) = least m such that if r and s in {1/1, 1/2, 1/3, ..., 1/n} satisfy r < s, then r < k/m < (k+2)/m < s for some integer k.at n=39A024840
- Primes of the form n^2 - 6.at n=10A028880
- 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 63.at n=21A031561
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 32 ones.at n=20A031800
- Lower prime of a difference of 10 between consecutive primes.at n=53A031928
- Primes of form x^2+95*y^2.at n=29A033206
- Binomial transform of A003603.at n=11A035530
- Coordination sequence T13 for Zeolite Code STT.at n=43A038420
- Numbers ending with '9' that are the difference of two positive cubes.at n=19A038864
- Primes of form abs(2*n^2-199).at n=42A039950
- Numbers whose base-5 representation contains exactly two 1's and three 3's.at n=22A045243
- Discriminants of imaginary quadratic fields with class number 15 (negated).at n=17A046012