2791
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2792
- 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
- 2790
- Möbius Function
- -1
- Radical
- 2791
- 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
- 66
- 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
- 406
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes with 6 as smallest primitive root.at n=24A001125
- Primes p such that the multiplicative order of 2 modulo p is (p-1)/6.at n=18A001136
- Cuban primes: primes which are the difference of two consecutive cubes.at n=16A002407
- Low temperature series for spin-1/2 Ising magnetic susceptibility on 2D square lattice.at n=6A002927
- Smallest number with reciprocal of period length n in decimal (base 10).at n=31A003060
- Hex (or centered hexagonal) numbers: 3*n*(n+1)+1 (crystal ball sequence for hexagonal lattice).at n=30A003215
- Smallest primitive factor of 10^n - 1. Also smallest prime p such that 1/p has repeating decimal expansion of period n.at n=30A007138
- Prime(n)*...*a(n) is the least product of consecutive primes which is non-deficient.at n=14A007686
- Prime(n)*...*a(n) is the least product of consecutive primes which is abundant.at n=14A007708
- Coordination sequence T2 for Zeolite Code APD.at n=35A008035
- Coordination sequence T2 for Zeolite Code LOV.at n=35A008135
- Coordination sequence T4 for Zeolite Code VET.at n=32A009905
- a(n) = prime(n*(n+1)/2).at n=27A011756
- Numbers k such that the continued fraction for sqrt(k) has period 84.at n=3A020423
- Primes that remain prime through 2 iterations of function f(x) = 4x + 9.at n=45A023251
- Primes that remain prime through 2 iterations of function f(x) = 6x + 1.at n=28A023256
- Primes that remain prime through 3 iterations of function f(x) = 4x + 9.at n=11A023282
- 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=34A024824
- Coordination sequence T1 for Zeolite Code IFR.at n=37A024982
- Coordination sequence T8 for Zeolite Code MWW.at n=35A024993