7087
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 7480
- Proper Divisor Sum (Aliquot Sum)
- 393
- 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
- 6696
- Möbius Function
- 1
- Radical
- 7087
- 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
- 57
- 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
- From expansion of falling factorials.at n=9A005492
- Pseudoprimes to base 88.at n=34A020216
- Fibonacci sequence beginning 1, 11.at n=15A022101
- Lucky numbers with size of gaps equal to 14 (lower terms).at n=35A031896
- Floor( 7*n^2/2 ).at n=45A032525
- Number of partitions of n with equal number of parts congruent to each of 2 and 3 (mod 5).at n=41A035559
- Numbers whose base-4 representation contains exactly three 2's and three 3's.at n=24A045151
- Odd composite numbers which in base 2 contain their largest proper factor as a substring of digits.at n=17A063131
- Composite numbers not divisible by 2, 3, 5 or 7 which in base 2 contain their largest proper factor as a substring.at n=13A063138
- Composite numbers which in base 8 contain their largest proper factor as a substring.at n=2A063167
- Duplicate of A063167.at n=2A063878
- Numbers k such that prime(k+2)-(k+2)*tau(k+2) = prime(k-2)-(k-2)*tau(k-2) where tau(k) = A000005(k) is the number of divisors of k.at n=25A067354
- a(n) = a(n-1) - a(n-2) + a(n-3) + a(n-4), a(0)=4, a(1)=1, a(2)=-1, a(3)=1.at n=36A073937
- Reflected tetranacci numbers A073817.at n=36A074058
- Semiprimes which are the sum of two pentagonal numbers (A000326) in exactly two different ways.at n=37A120536
- a(n) = first term that can be reduced in n steps via repeated interpretation of a(n) as a base b+1 number where b is the largest digit of a(n), such that b is always 8 so that each interpretation is base 9. Terms already fully reduced (i.e., single digits) are excluded.at n=4A141842
- 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, 0), (-1, 0, -1), (-1, 0, 0), (1, -1, 1), (1, 1, 0)}.at n=8A149191
- Composite numbers n such that 8*n^2-2*n-1 divides the primitive part U(n) of Fibonacci(n).at n=12A159234
- Positive numbers n such that 8*n^2-2*n-1 divides Fibonacci(n).at n=39A159259
- Inverse permutation to A190128.at n=18A190129