7019
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7020
- 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
- 7018
- Möbius Function
- -1
- Radical
- 7019
- 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
- 44
- 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
- 903
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) = prime(n*(n+1)/2).at n=41A011756
- Fibonacci sequence beginning 1, 18.at n=14A022108
- Primes that remain prime through 3 iterations of function f(x) = 3x + 10.at n=39A023280
- Convolution of the lower and upper Wythoff sequences (A000201 and A001950).at n=20A023664
- 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=14A031581
- Number of n-node rooted identity trees of height 8.at n=8A038092
- Primes with first digit 7.at n=20A045713
- T(n,n+2), array T as in A047089.at n=7A047096
- a(n) = Sum_{i=0..n} T(i,n-i), array T as in A049687.at n=40A049688
- Primes remaining prime if any digit is deleted (zeros allowed).at n=26A051362
- Primes p such that x^29 = 2 has no solution mod p.at n=28A059256
- a(n) = floor( n^e ), e = 2.718281828...at n=25A061293
- Primes p such that p^6 + p^3 + 1 is prime.at n=37A066100
- Group successively larger prime numbers so that the sum of the n-th group is a multiple of n. Sequence gives the first term of each group.at n=40A074129
- Primes of the form floor(n^e).at n=5A074222
- Initial terms of groups in A075639.at n=42A075641
- Primes p such that A001414(p-1) and A001414(p+1) are both prime, where A001414 = sum of primes dividing n (with repetition).at n=36A086715
- Least initial value for a Euclid/Mullin sequence whose 3rd term (= least prime divisor of 1+2p) equals the n-th prime. prime(1)=2 is never a third term, so offset=2.at n=24A094464
- Numbers that reach the fixed point 89 under iteration of f(x) = reverse(x) - maxdigit(x).at n=8A097155
- Primes from merging of 4 successive digits in decimal expansion of Pi.at n=14A104824