2490
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 6048
- Proper Divisor Sum (Aliquot Sum)
- 3558
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 656
- Möbius Function
- 1
- Radical
- 2490
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 89
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- a(n) = a(n-1) + a(n-9) for n >= 9; a(n) = 1 for n=0..7; a(8) = 2.at n=44A005711
- Coordination sequence T2 for Zeolite Code AFS.at n=38A008024
- Coordination sequence T2 for Zeolite Code BPH.at n=38A008056
- Coordination sequence T1 for Zeolite Code MTN.at n=30A008186
- Expansion of 1/(1 - x^9 - x^10 - ...).at n=54A017903
- Coordination sequence T4 for Zeolite Code SAO.at n=39A019574
- a(n) = prime(n)*prime(n-1) - 1.at n=15A023515
- Second elementary symmetric function of 3,4,...,n+3.at n=8A024183
- Numbers k such that the decimal expansion of k^3 contains k as a substring.at n=50A029942
- Every run of digits of n in base 9 has length 2.at n=29A033007
- Numbers whose base-9 expansion has no run of digits with length < 2.at n=40A033022
- Coordination sequence T3 for Zeolite Code CFI.at n=33A033601
- Triangular array read by rows associated with Schroeder numbers: T(1,k) = 1; T(n,k) = 0 if k < n; T(n,k) = T(n,k-1) + T(n-1,k-1) + T(n-1,k).at n=40A033877
- a(n)-th prime is the smallest prime containing exactly n 2's.at n=4A037056
- Coordination sequence T6 for Zeolite Code STT.at n=33A038421
- Numbers whose base-3 representation has exactly 8 runs.at n=10A043588
- Numbers whose number of runs in base 3 is congruent to 1 (mod 7).at n=24A043792
- Numbers n such that number of runs in the base 3 representation of n is congruent to 0 mod 8.at n=10A043798
- Numbers n such that number of runs in the base 3 representation of n is congruent to 8 mod 9.at n=10A043814
- Numbers k such that number of runs in the base 3 representation of k is congruent to 8 mod 10.at n=10A043823