2027
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2028
- 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
- 2026
- Möbius Function
- -1
- Radical
- 2027
- 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
- 156
- 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
- yes
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 307
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Safe primes p: (p-1)/2 is also prime.at n=37A005385
- a(n) = floor(tau*a(n-2)) + a(n-1) with a(0)=1 and a(1)=3.at n=12A005907
- From relations between Siegel theta series.at n=20A006476
- Where the prime race among 5k+1, ..., 5k+4 changes leader.at n=18A007353
- Primes of form x^3 + y^3 + z^3 where x,y,z > 0.at n=46A007490
- Smallest prime > n^2.at n=44A007491
- Coordination sequence T2 for Zeolite Code AET.at n=31A008008
- Coordination sequence T3 for Zeolite Code EPI.at n=28A008092
- Least m such that if a/b < c/d are Farey fractions of order n then there exists k such that a/b < k/m < c/d, k/m reduced.at n=51A009571
- a(0) = 1, a(n) = n^2 + 2 for n > 0.at n=45A010000
- a(0) = 1, a(n) = 9*n^2 + 2 for n>0.at n=15A010002
- a(0) = 1, a(n) = 25*n^2 + 2 for n > 0.at n=9A010015
- Least d such that period of continued fraction for sqrt(d) contains n (n^2+2 if n odd, (n/2)^2+1 if n even).at n=44A013945
- Primes that remain prime through 2 iterations of function f(x) = 2x + 3.at n=35A023242
- Primes that remain prime through 2 iterations of function f(x) = 8x + 1.at n=9A023260
- Primes that remain prime through 2 iterations of function f(x) = 9x + 8.at n=29A023267
- a(n) = least m such that if r and s in {h/(1 + h^2): h = 1,2,...,n} satisfy r < s, then r < k/m < s for some integer k.at n=50A024828
- Sequence satisfies T^2(a)=a, where T is defined below.at n=43A027590
- Squarefree n such that Q(sqrt(n)) has class number 5.at n=15A029705
- Primes p such that digits of p appear in p^2.at n=40A030079