2279
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2376
- Proper Divisor Sum (Aliquot Sum)
- 97
- 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
- 2184
- Möbius Function
- 1
- Radical
- 2279
- 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
- 151
- 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
- Number of compositions of n into a sum of odd primes.at n=36A002124
- Numbers of the form (p^2 - 49)/120 where p is prime.at n=48A002382
- Odd numbers not of form p + 2^k (de Polignac numbers).at n=52A006285
- Number of planted 3-trees of height < n.at n=5A006894
- Coordination sequence T1 for Zeolite Code AFT.at n=36A008026
- Coordination sequence T2 for Zeolite Code AFT.at n=36A008027
- Coordination sequence T2 for Zeolite Code DDR.at n=30A008072
- Coordination sequence T2 for Zeolite Code AFX.at n=36A009865
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n+1-k), where k = [ (n+1)/2 ], s = A000201 (lower Wythoff sequence).at n=20A024685
- a(n) = least m such that if r and s in {1/1, 1/3, 1/5,..., 1/(2n-1)} satisfy r < s, then r < k/m < s for some integer k.at n=38A024819
- a(n) = least m such that if r and s in {1/1, 1/2, 1/3, ..., 1/n} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=36A024833
- a(n) = least m such that if r and s in {1/2, 1/4, 1/6, ..., 1/(2*n)} satisfy r < s, then r < k/m < (k+3)/m < s for some integer k.at n=17A024845
- In base 11, a(n) = sum of digits of Lucas(a(n)).at n=29A025491
- The "semi-Fibonacci numbers": a(n) = A030067(2n - 1), where A030067 is the semi-Fibonacci sequence.at n=54A030068
- First occurrence of n as a term in the continued fraction for zeta(3).at n=36A033165
- Number of partitions satisfying (cn(2,5) = cn(3,5) = 0 and cn(0,5) <= cn(1,5) and cn(0,5) <= cn(4,5)).at n=48A036823
- a(n)=(s(n)+6)/9, where s(n)=n-th base 9 palindrome that starts with 3.at n=30A043074
- Numbers k such that string 4,7 occurs in the base 8 representation of k but not of k-1.at n=39A044226
- Numbers n such that string 1,2 occurs in the base 9 representation of n but not of n-1.at n=31A044262
- Numbers n such that string 7,9 occurs in the base 10 representation of n but not of n-1.at n=24A044411