1249
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
- 1250
- 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
- 1248
- Möbius Function
- -1
- Radical
- 1249
- 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
- 176
- 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
- 204
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of simplicial polyhedra with n vertices; simple planar graphs with n vertices and 3n-6 edges; maximal simple planar graphs with n vertices; planar triangulations with n vertices; triangulations of the sphere with n vertices; 3-connected cubic planar graphs on 2n-4 vertices.at n=8A000109
- Numbers m such that Fibonacci(m) ends with m.at n=35A000350
- Primes p of the form 3k+1 such that sum_{x=1..p} cos(2*Pi*x^3/p) < -sqrt(p).at n=17A000923
- Primes with 7 as smallest primitive root.at n=12A001126
- Numbers that are the sum of 8 positive 5th powers.at n=44A003353
- Numbers that are the sum of 9 positive 5th powers.at n=48A003354
- a(n) = ceiling(n*phi^7), where phi is the golden ratio, A001622.at n=43A004962
- Primes of form x^3 + y^3 + z^3 where x,y,z > 0.at n=34A007490
- Primes of form 8n+1, that is, primes congruent to 1 mod 8.at n=46A007519
- Prime(n)*...*a(n) is the least product of consecutive primes which is non-deficient.at n=10A007686
- Prime(n)*...*a(n) is the least product of consecutive primes which is abundant.at n=10A007708
- Primes p == 1 (mod 8), p = a^2 + 64*b^2 such that y^2 = x^3 + p*x has rank 2.at n=16A007766
- Coordination sequence T3 for Zeolite Code EMT.at n=29A008088
- Coordination sequence T3 for Zeolite Code CON.at n=25A009870
- Coordination sequence T3 for Zeolite Code RSN.at n=23A009887
- Least m such that the continued fraction for sqrt(m) has period n.at n=45A013646
- a(n) is prime and sum of all primes <= a(n) is prime.at n=24A013917
- From table of maximal epacts e(p) and corresponding primes p, for x_0=2, x_{m+1} = (x_m)^2-1; sequence gives p.at n=19A014426
- Primes p==1 (mod 6) such that 3 and -3 are both cubes (one implies other) modulo p.at n=30A014753
- Primes p == 1 mod 8 such that 2 and -2 are both 4th powers (one implies other) mod p.at n=21A014754