7775
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 9672
- Proper Divisor Sum (Aliquot Sum)
- 1897
- 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
- 6200
- Möbius Function
- 0
- Radical
- 1555
- Omega Function (Ω)
- 3
- 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
- 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
- no
- Odd
- yes
Appears in sequences
- Numbers k that divide 6^k-1.at n=7A014946
- Positive numbers k such that k = x^5 + y^5 has a solution in nonzero integers x, y.at n=29A020896
- a(n) = 6^n - 1.at n=5A024062
- a(n) = (n+1)^n - 1.at n=5A037205
- Shifts left under transform T where Ta is phi DCONV a.at n=48A038045
- Numerators of continued fraction convergents to sqrt(69).at n=7A041120
- Numerators of continued fraction convergents to sqrt(276).at n=11A041518
- Numerators of continued fraction convergents to sqrt(621).at n=5A042192
- Numbers having three 7's in base 10.at n=26A043519
- Numbers that are repdigits in base 6.at n=25A048331
- Duplicate of A037205.at n=5A060071
- Nonprime solutions to k == -1 (mod phi(k+1)).at n=31A067930
- Numbers k such that phi(k) is a harmonic number.at n=46A074244
- a(n) is smallest natural number a satisfying Pell equation a^2 - d(n)*b^2= +1 or = -1, with d(n)=A000037(n) (a nonsquare). Corresponding smallest b(n)=A077233(n).at n=60A077232
- Numbers k such that 11*12^k - 1 is prime.at n=12A079907
- 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=17A080524
- Triangular array T of numbers generated by these rules: 1 is in T; and if x is in T, then 2x+1 and 3x+2 are in T.at n=50A094615
- A card-arranging problem: values of n such that there exists a permutation p_1, ..., p_n of 1, ..., n such that i + p_i is a fifth power for every i.at n=30A096906
- Numbers whose set of base 6 digits is {0,5}.at n=31A097252
- Row sums of the triangle of triangular binomial coefficients given by A098568.at n=8A098569