2927
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2928
- 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
- 2926
- Möbius Function
- -1
- Radical
- 2927
- 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
- 172
- 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
- 423
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of n-step spiral self-avoiding walks on hexagonal lattice, where at each step one may continue in same direction or make turn of 2*Pi/3 counterclockwise.at n=26A000511
- Number of paraffins.at n=22A005998
- Coordination sequence T1 for Zeolite Code AFR.at n=41A008019
- a(0) = 1, a(n) = 13*n^2 + 2 for n>0.at n=15A010004
- Numbers n such that phi(n + 9) | sigma(n) for n not congruent to 0 (mod 3).at n=46A015849
- Numbers k such that the continued fraction for sqrt(k) has period 36.at n=36A020375
- Primes that remain prime through 2 iterations of function f(x) = 2x + 3.at n=44A023242
- Primes that remain prime through 2 iterations of function f(x) = 4x + 9.at n=48A023251
- Primes that remain prime through 2 iterations of function f(x) = 8x + 1.at n=13A023260
- Primes that remain prime through 3 iterations of function f(x) = 8x + 1.at n=3A023291
- 4th elementary symmetric function of the first n+3 primes.at n=1A024449
- a(n) is the numerator of Sum_{i = 1..n} 1/prime(i).at n=5A024451
- a(n) = least m such that if r and s in {1/1, 1/3, 1/5,..., 1/(2n-1)} satisfy r < s, then r < k/m < s for some integer k.at n=43A024819
- Primes p such that digits of p appear in p^2 and p^3.at n=21A030085
- Smallest nontrivial extension of n-th palindrome which is a prime.at n=37A030675
- Positions of record values in A030777.at n=47A030782
- 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 53.at n=11A031551
- a(n) = prime(10*n-7).at n=42A031917
- Upper prime of a difference of 10 between consecutive primes.at n=40A031929
- Lower prime of a difference of 12 between consecutive primes.at n=27A031930