7039
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7040
- 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
- 7038
- Möbius Function
- -1
- Radical
- 7039
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 80
- 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
- 905
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) is the least prime > a(n-1) whose digits do not appear in a(n-1).at n=23A030284
- 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=17A031581
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 60 ones.at n=8A031828
- Shifts left 2 places under "CGK" (necklace, element, unlabeled) transform.at n=18A032162
- Trajectory of 48 under prime factor concatenation procedure.at n=26A037941
- Sums of 11 distinct powers of 2.at n=25A038462
- Primes p such that x^23 = 2 has no solution mod p.at n=42A040984
- Numbers whose base-4 representation contains exactly two 1's and four 3's.at n=31A045123
- Primes with first digit 7.at n=22A045713
- Euclid-Mullin sequence (A000945) with initial value a(1)=71 instead of a(1)=2.at n=21A051324
- Least prime in A023200 (lesser of 4-twins) such that the distance to the next 4-twin is 6*n.at n=27A052351
- a(0)=0, a(1)=2, a(n) = smallest prime > a(n-1)+a(n-2).at n=17A055502
- Primes of the form sum 6d/(2 + mu(d)) for some k and all d dividing k.at n=20A069548
- Right diagonal of triangle in A072467.at n=16A072469
- a(n) = prime(n*(n+1)/2+2).at n=42A078722
- a(n) = 6*n^2 + 3*n + 1.at n=34A085473
- a(n) is the largest prime factor of 2^n + 3^n.at n=16A094474
- Primes with two 0-bits in their binary expansion.at n=42A095079
- Slowest increasing sequence in which a(n) is a prime closest to the sum of all previous terms.at n=13A109277
- Rearrangement of primes (other than 2 and 5) so that the unit digit follows the pattern 1,3,7,9,1,3,7,9,... and every partial concatenation is prime.at n=35A110798