2149
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
- 4
- Divisor Sum
- 2464
- Proper Divisor Sum (Aliquot Sum)
- 315
- 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
- 1836
- Möbius Function
- 1
- Radical
- 2149
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 24
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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 k such that (1,k) is "good".at n=30A000696
- Number of sublattices of index n in generic 3-dimensional lattice.at n=33A001001
- Positions of remoteness 5 in Beans-Don't-Talk.at n=45A005697
- Coordination sequence T2 for Zeolite Code NON.at n=28A008213
- Expansion of (1+x^7)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=52A008768
- Coordination sequence T3 for Zeolite Code -PAR.at n=33A009857
- Positive integers n such that 2^n == 2^7 (mod n).at n=51A015927
- Conjectured formula for irreducible 6-fold Euler sums of weight 2n+16.at n=17A019459
- Pseudoprimes to base 17.at n=14A020145
- Pseudoprimes to base 18.at n=20A020146
- Numbers k such that the continued fraction for sqrt(k) has period 84.at n=2A020423
- Integer part of (4th elementary symmetric function of 3,4,...,n+5)/(3+4+...+n+5).at n=4A024192
- Number of partitions of n into distinct parts, the least being odd.at n=49A026832
- a(n) = Sum_{k=0..2n} (k+1) * A027113(n, k).at n=5A027137
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 38 ones.at n=1A031806
- If d,e are consecutive digits of n in base 7, then |d-e|>=5.at n=26A032995
- Multiplicity of highest weight (or singular) vectors associated with character chi_43 of Monster module.at n=33A034431
- Number of partitions of n into parts not of the form 25k, 25k+10 or 25k-10. Also number of partitions with at most 9 parts of size 1 and differences between parts at distance 11 are greater than 1.at n=25A036009
- Number of permutations P of {1,2,...,n} such that P(1)=1 and |P^-1(i+1)-P^-1(i)| equals 1 or 2 for i=1,2,...,n-1.at n=19A038718
- Denominators of continued fraction convergents to sqrt(127).at n=6A041231