2558
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
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3840
- Proper Divisor Sum (Aliquot Sum)
- 1282
- 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
- 1278
- Möbius Function
- 1
- Radical
- 2558
- 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
- yes
- Odd
- no
Appears in sequences
- Alkyl naphthalenes C_{n+10} H_{2n+8} with n+10 carbon atoms.at n=7A000647
- Numbers k such that phi(2k-1) < phi(2k), where phi is Euler's totient function A000010.at n=38A001836
- G.f.: 1/Product_{k>=1} (1-prime(k)*x^prime(k)).at n=16A002098
- Coordination sequence T2 for Zeolite Code LAU.at n=36A008125
- Coordination sequence T4 for Zeolite Code MFS.at n=31A008176
- Molien series for Weyl group E_8.at n=56A008582
- If a, b in sequence, so is ab+10.at n=18A009368
- a(n) = floor( n*(n-1)*(n-2)/25 ).at n=41A011907
- Coordination sequence T2 for Zeolite Code CGF.at n=35A019452
- Coordination sequence T3 for Zeolite Code CGF.at n=35A019453
- Coordination sequence T3 for Zeolite Code CZP.at n=33A019458
- Place where n-th 1 occurs in A023127.at n=45A022789
- Convolution of odd numbers and A001950.at n=13A023659
- a(n) = Sum{k=0..n} T(n,k), T given by A026747.at n=10A026754
- Number of partitions of n into an odd number of parts, the least being 4; also, a(n+4) = number of partitions of n into an even number of parts, each >=4.at n=57A027190
- Numbers m such that (1+i)^m + i is a Gaussian prime.at n=27A027206
- a(n) = n^2 + n + 8.at n=50A027693
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 50.at n=5A031548
- a(n) = 2*n^2 + 3*n + 3.at n=35A033816
- Shifts left under transform T where Ta is (identity) DCONV a.at n=26A038046