7159
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
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7160
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 7158
- Möbius Function
- -1
- Radical
- 7159
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 75
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 916
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Eleven iterations of Reverse and Add are needed to reach a palindrome.at n=9A015992
- Sums of six consecutive squares: a(n) = n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2 + (n+5)^2.at n=32A027865
- Primes of the form n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2 + (n+5)^2.at n=11A027867
- 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 83.at n=27A031581
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 68 ones.at n=3A031836
- Lower prime of a difference of 18 between consecutive primes.at n=27A031936
- Number of partitions of n such that cn(3,5) <= cn(0,5) = cn(1,5) < cn(2,5) = cn(4,5).at n=70A036868
- Sums of 11 distinct powers of 2.at n=29A038462
- Numbers whose base-4 representation contains exactly two 1's and four 3's.at n=33A045123
- Primes with first digit 7.at n=33A045713
- Sequence of 2 Pythagorean triangles, each with a leg and hypotenuse prime. The leg of the second triangle is the hypotenuse of the first.at n=27A048270
- Prime number spiral (clockwise, South spoke).at n=15A054566
- Hard numbers: a(n) = smallest positive number m with f(m) = n, where f(m) is the smallest number of digits that are needed to construct m using only 1's, 2's and any number of +, -, *, ^ signs, allowing concatenation of the digits.at n=9A060273
- Numbers which need eleven 'Reverse and Add' steps to reach a palindrome.at n=8A065216
- The first of two consecutive primes with equal digital sums.at n=19A066540
- First minimum value > 0 of the form x^3-k^2 when k > n^3.at n=18A070959
- Numbers k such that Lucas(2k)/3 is prime.at n=18A074304
- Sum of first n perfect powers.at n=33A076408
- Number of triangular partitions of n of order 4.at n=15A084446
- Beginning with 1, minimum value such that gcd(a(2n-1),a(2n)) = 1, gcd(a(2n),a(2n+1))>1 and a(n) > a(n-1).at n=49A091856