2089
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
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2090
- 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
- 2088
- Möbius Function
- -1
- Radical
- 2089
- 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
- 63
- 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
- 316
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes with 7 as smallest primitive root.at n=17A001126
- Generalized divisor function. Number of partitions of n with exactly three part sizes.at n=30A002134
- a(n) = largest noncomposite factor of 2^(2n+1) - 1.at n=14A002588
- Largest prime factor of n-th Mersenne number (A001348(n)).at n=9A003260
- Divisors of 2^29 - 1.at n=3A003537
- a(n) = 5*a(n-1) - a(n-2), with a(1)=1, a(2)=4.at n=5A004253
- Let i, i+d, i+2d, ..., i+(n-1)d be an n-term arithmetic progression of primes; choose the one which minimizes the last term; then a(n) = last term i+(n-1)d.at n=9A005115
- Largest prime factor of 2^n - 1.at n=27A005420
- Number of paraffins.at n=16A006001
- From relations between Siegel theta series.at n=23A006476
- Primes p == 1 (mod 8), p = a^2 + 64*b^2 such that y^2 = x^3 + p*x has rank 2.at n=27A007766
- Coordination sequence T3 for Zeolite Code ATS.at n=33A008040
- Coordination sequence T1 for Zeolite Code LEV.at n=34A008127
- Coordination sequence for alpha-Mn, Position Mn2.at n=12A009951
- Primes p == 1 mod 8 such that 2 and -2 are both 4th powers (one implies other) mod p.at n=34A014754
- Six iterations of Reverse and Add are needed to reach a palindrome.at n=42A015984
- Numbers k=3*m+1 such that 2^m == 1 (mod k).at n=50A016108
- Powers of fourth root of 5 rounded down.at n=19A018057
- Numbers k such that the continued fraction for sqrt(k) has period 21.at n=14A020360
- Primes that remain prime through 2 iterations of function f(x) = 6x + 7.at n=34A023258