7779
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 30
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 10376
- Proper Divisor Sum (Aliquot Sum)
- 2597
- 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
- 5184
- Möbius Function
- 1
- Radical
- 7779
- 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
- 39
- 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
- no
- Odd
- yes
Appears in sequences
- A generalized Fibonacci sequence.at n=50A001584
- Least term in period of continued fraction for sqrt(n) is 5.at n=28A031429
- 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 29.at n=31A031527
- Lucky numbers that are concatenations of n with n + 2.at n=9A032652
- Number of partitions of n with equal number of parts congruent to each of 0, 2 and 3 (mod 5).at n=52A035575
- Numbers having four 0's in base 6.at n=7A043372
- Numbers having three 7's in base 10.at n=29A043519
- Integers n > 7059 such that the 'Reverse and Add!' trajectory of n joins the trajectory of 7059.at n=7A063058
- C(n+3)=2*C(n), where C(n) is Cototient(n) := n - phi(n) (A051953).at n=43A063480
- Triangle read by rows in which the n-th row contains n distinct numbers whose sum is n^n. The numbers are terms of an arithmetic progression with a common difference 1 or 2 respectively accordingly as n is odd or even.at n=19A080524
- Values of k such that floor(k*tanh(Pi)) = floor((k+1) tanh(Pi)).at n=28A096613
- a(n) = 3*(2*n^2 + 1).at n=36A097803
- Indices of primes in sequence defined by A(0) = 97, A(n) = 10*A(n-1) - 33 for n > 0.at n=23A101005
- Near-repdigit semiprimes with 7 as repeated digit.at n=19A105988
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 1), (0, 1, -1), (0, 1, 1), (1, 0, 1)}.at n=7A150547
- Similar to A072921 but starting with 3.at n=35A152232
- Numbers k such that k^2 == 2 (mod 23^2).at n=29A156849
- a(n) = smallest number that leads to a new cycle under the base-6 Kaprekar map of A165051.at n=6A165068
- a(n) = (7*10^n + 11)/9 for n > 0.at n=3A173808
- Numbers k such that (k^3 + 2, n^3 + 4) is a twin prime pair.at n=44A178337