7890
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 19008
- Proper Divisor Sum (Aliquot Sum)
- 11118
- 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
- 2096
- Möbius Function
- 1
- Radical
- 7890
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 101
- 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
- Icosahedral numbers: a(n) = n*(5*n^2 - 5*n + 2)/2.at n=14A006564
- Expansion of Product_{m>=1} (1 - m*q^m)^5.at n=16A022665
- a(n) = floor(floor(S3)/floor(S1)), where S3 and S1 are, respectively, the 3rd and first elementary symmetric functions of {sqrt(k), k = 1,2,...,n}.at n=45A025200
- Numbers k such that 161*2^k-1 is prime.at n=18A050832
- Numbers in which each digit is the (immediate) successor of the previous one (if it exists) and 0 is considered the successor of 9.at n=34A059043
- Coefficients in expansion of Sum_{n >= 1} x^n/(1-x^n)^4.at n=35A059358
- Seventh column (m=6) of convolution triangle A059594(n,m).at n=7A059595
- a(n) is an n-digit number with digits in increasing order with 0 following 9 and this is maintained in the concatenation of any number of consecutive terms.at n=3A062273
- a(n) = Sum_{i=1..n} binomial(i+5,6)^2.at n=3A086027
- a(n) = -1/16-3*n^2/8+17*n/12+n^3/12+(-1)^n/16.at n=46A088795
- Smallest available integer which fits into the repeating pattern 0123456789.at n=21A098755
- Slowest increasing sequence with its first 10 digits all different one from another, then the next 10, then the next 10, etc.at n=26A106604
- a(n)=a(n-1)+sum of digits(a(n-1))*sum of digits(a(n-2)).at n=32A108720
- Number triangle of sums of squared binomial coefficients.at n=51A110197
- Square array of Kekulé numbers for the mirror-symmetrical chevrons Ch(m,n), read by antidiagonals (m,n >= 0).at n=62A123349
- Kekulé numbers for certain benzenoids (see the Cyvin-Gutman book for details).at n=7A123351
- Triangle read by rows: T(n,k) = binomial(n,k) + 2^k*binomial(n,k+1) (0 <= k <= n).at n=61A125103
- Binomial transform of [1, 2, 3, 4, 0, 0, 0, ...].at n=23A139488
- Positions of harmonic numbers in the EKG sequence.at n=11A140804
- Triangle read by rows: expansion of p(x,n)=If[n == 0, 1, (x + 1)^n + 2^(n-1)*Sum[Binomial[n-m, m]*x^m*(1 + x^(n - 2*m)), {m, 1, n - 1}]].at n=59A146772