7888
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 31
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 20
- Divisor Sum
- 16740
- Proper Divisor Sum (Aliquot Sum)
- 8852
- 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
- 3584
- Möbius Function
- 0
- Radical
- 986
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 52
- 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
- Coefficients of ménage hit polynomials.at n=5A000159
- Generalized tangent numbers d_(n,2).at n=12A000176
- Latest possible occurrence of the first consecutive pair of n-th power residues, modulo any prime.at n=3A000445
- Expansion of sin(x)*cos(sin(x)).at n=4A009533
- Expansion of e.g.f. sinh(x)*exp(sinh(x)).at n=9A009623
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite MOR = Mordenite Na8[Al8Si40O96].24H2O starting with a T4 atom.at n=12A019182
- a(n) = number of (s(0), s(1), ..., s(2n)) such that s(i) is a nonnegative integer and |s(i) - s(i-1)| = 1 for i = 1,2,...,n, s(0) = 3, s(2n) = 7. Also a(n) = T(2n,n-2), where T is defined in A026022.at n=6A026031
- Numbers having three 8's in base 10.at n=7A043523
- T(n,k)=S(2n+2,n-1,k-1), 0<=k<=n, n >= 0, array S as in A050157.at n=32A050162
- Iterated procedure 'composite k added to sum of its prime factors reaches a prime' yields 9 skipped primes.at n=42A050776
- 16-gonal (or hexadecagonal) numbers: a(n) = n*(7*n-6).at n=34A051868
- a(n) contains n digits (either '7' or '8') and is divisible by 2^n.at n=3A053379
- Triangle read by rows, giving coefficients of the ménage hit polynomials ordered by descending powers. T(n, k) for 0 <= k <= n.at n=41A058087
- Numbers n such that phi(n) = product of the digits of n.at n=13A058627
- Smallest multiple of 8 with digit sum n.at n=31A069536
- Binomial transform of expansion of cosh(sinh(x)).at n=9A081443
- a(n) = sum of the first n lower twin primes.at n=29A086167
- Natural numbers written out with their digits grouped in sets of four (leading zeros omitted).at n=41A091332
- Triangle read by rows: T(n,k) = number of ways of seating n couples around a circular table so that exactly k married couples are adjacent (0 <= k <= n).at n=39A094314
- Triangle T(n, k) = coefficients of p(n,x), where p(n,x) = Sum_{j=0..n} (2*n*(n-j)!/(2*n-j)) * binomial(2*n-j, j) * (x-1)^j and p(0,x) = 1, read by rows.at n=39A156996