7027
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7028
- 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
- 7026
- Möbius Function
- -1
- Radical
- 7027
- 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
- 57
- 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
- 904
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) = floor( n*(n-1)*(n-2)/20 ).at n=53A011902
- Numbers k such that the continued fraction for sqrt(k) has period 94.at n=12A020433
- Size of lexicographic code of length n, Hamming distance 6 and weight 6.at n=41A031504
- 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=15A031581
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 46 ones.at n=23A031814
- Primes with first digit 7.at n=21A045713
- Discriminants of imaginary quadratic fields with class number 11 (negated).at n=26A046008
- Primes for which only two iterations of 'Prime plus its digit sum equals a prime' are possible.at n=36A048524
- Primes p such that p^6 reversed is also prime.at n=35A059699
- Primes starting and ending with 7.at n=5A062334
- a(n) = prime(n*(n+1)/2 + 1).at n=42A078721
- Primes equal to floor(Pi*x) where x is prime.at n=45A079593
- a(1) = 1 and then the smallest primes such that all a(k)-a(j) are distinct composite numbers.at n=38A079850
- Number of partitions of n having positive even rank (the rank of a partition is the largest part minus the number of parts).at n=39A101708
- Primes one less than the sum over a sexy prime pair.at n=48A104227
- Primes from merging of 4 successive digits in decimal expansion of e.at n=37A104845
- a(n) = 2*a(n-2)+5*a(n-3), n>6.at n=15A107229
- Numbers k such that k*(k+8) gives the concatenation of two numbers m and m+2.at n=2A116305
- Primes for which the weight as defined in A117078 is 23.at n=14A119504
- Triangle read by rows: T(n,k) is the number of deco polyominoes of height n having k cells in the second column (n>=1, k>=0). A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.at n=33A121581