4240
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 20
- Divisor Sum
- 10044
- Proper Divisor Sum (Aliquot Sum)
- 5804
- 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
- 1664
- Möbius Function
- 0
- Radical
- 530
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 3
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
- 126
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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) = 2^n + n^2.at n=12A001580
- a(n) = Fibonacci(n+2) + prime(n).at n=16A004399
- Coordination sequence T7 for Zeolite Code MTT.at n=40A008195
- Coordination sequence T3 for Zeolite Code iRON.at n=45A009883
- Coordination sequence for FeS2-Marcasite, Fe position.at n=34A009955
- arctanh(sin(arcsinh(x)))=x+4/5!*x^5-80/7!*x^7+4240/9!*x^9-342400/11!*x^11...at n=4A012042
- Numbers k such that phi(k) + 10 | sigma(k).at n=8A015801
- n written in fractional base 6/4.at n=24A024637
- a(n) = (d(n)-r(n))/2, where d = A026066 and r is the periodic sequence with fundamental period (1,0,0,0).at n=25A026067
- a(0) = a(1) = 1; a(n+2) = 2*a(n+1) + 2*a(n).at n=9A026150
- Numbers k such that A102489(k) is divisible by k.at n=20A032563
- XOR-convolution of squares A000290 with themselves.at n=18A033460
- Second pentagonal numbers with odd index: a(n) = (2*n-1)*(3*n-1).at n=27A033568
- Number of binary [ n,3 ] codes without 0 columns.at n=23A034344
- Triangle of coefficients arising in calculation of A002872 and A002874 (sorting numbers).at n=39A036073
- Numbers whose base-4 representation contains exactly four 0's and two 1's.at n=25A045035
- Let (u1,u2) be successive untouchable numbers such that phi(u1) = phi(u2) = k; sequence gives values of k.at n=25A048191
- a(n) = Sum_{i=1..n} T(i,n-i), where T is A049615.at n=37A049616
- The number phi_3(n) of Frobenius partitions that allow up to 3 repetitions of an integer in a row.at n=19A053992
- a(n) = Sum_{k = 1..n, gcd(k,n)=1} k*(n-k).at n=39A057789