2509
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
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2716
- Proper Divisor Sum (Aliquot Sum)
- 207
- 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
- 2304
- Möbius Function
- 1
- Radical
- 2509
- 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
- 133
- 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
- A Fielder sequence. a(n) = a(n-1) + a(n-3) + a(n-4) + a(n-5), n >= 6.at n=14A001639
- Numbers that are the sum of 10 positive 6th powers.at n=35A003366
- a(n) = ceiling(n*phi^9), where phi is the golden ratio, A001622.at n=33A004964
- Coordination sequence T1 for Zeolite Code ATV.at n=32A008043
- Coordination sequence T2 for Zeolite Code iRON.at n=35A009882
- Coordination sequence T4 for Zeolite Code RSN.at n=33A009888
- Define the generalized Pisot sequence T(a(0),a(1)) by: a(n+2) is the greatest integer such that a(n+2)/a(n+1) < a(n+1)/a(n). This is T(3,5).at n=21A018917
- Pseudoprimes to base 49.at n=43A020177
- Pseudoprimes to base 63.at n=12A020191
- Pseudoprimes to base 84.at n=10A020212
- Pseudoprimes to base 85.at n=27A020213
- Strong pseudoprimes to base 63.at n=6A020289
- Numbers k such that the continued fraction for sqrt(k) has period 31.at n=7A020370
- Number of 3's in n-th term of A022482.at n=31A022486
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n-k+1), where k = floor( n/2 ), s = natural numbers >= 3.at n=25A024875
- Coordination sequence T1 for Zeolite Code IFR.at n=35A024982
- A B_2 sequence: a(n) is the least value such that sequence increases and pairwise sums of elements are all distinct.at n=38A025582
- Triangle read by rows: square of the lower triangular mean matrix.at n=39A027446
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 33.at n=0A031621
- Number of connected functions of n points with no symmetries.at n=11A032175