6919
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 8208
- Proper Divisor Sum (Aliquot Sum)
- 1289
- 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
- 5760
- Möbius Function
- -1
- Radical
- 6919
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- 225
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 23 (most significant digit on right).at n=13A029516
- Number of chiral noninvertible prime knots with n crossings.at n=12A051766
- Number of noninvertible prime knots with n crossings (A002863-A052402).at n=12A052403
- Smallest number which requires n^2 steps in the 3x+1 problem.at n=15A066773
- Position of A075165(n+1) in A014486.at n=45A075161
- Position of A075165(n) in A014486 plus one.at n=28A075163
- Numbers k such that 1.2. ... .k-1.k + 4 is a prime (dot between numbers means concatenation).at n=4A099084
- Positions of 9 in partition of decimal expansion of Pi A104807.at n=20A104809
- Numbers k such that k-th semiprime == 5 (mod k).at n=4A106130
- Position of A106455(n) in A014486 plus one.at n=40A106453
- Numbers k such that (2*k)!/(2*(k!)^2)+1 is prime.at n=36A112863
- Triangle V, read by rows, where column k of V^(j+1) = column j of P^(3k+2), for j>=0, k>=0 and where P=A136220.at n=41A136230
- Expansion of (1 + x*c(x))/(1 - x), where c(x) is the g.f. of A000108.at n=10A155587
- Integers n such that A000009(n) (the number of partitions of n into distinct parts) == 1 (mod n).at n=6A162468
- Integers of the form (k+1)*(2k+1)/12.at n=33A164578
- Multiples of 17 whose reversal + 1 is also a multiple of 17.at n=22A166391
- Partial sums of A097331; binomial transform of A166587.at n=19A166588
- Partial sums of A097331; binomial transform of A166587.at n=20A166588
- a(n) = n*(2 + 5*n).at n=37A168668
- Numbers k such that 12321*2^k + 1 is prime.at n=24A180924