7759
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7760
- 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
- 7758
- Möbius Function
- -1
- Radical
- 7759
- 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
- 145
- 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
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 985
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Where the prime race among 7k+1, ..., 7k+6 changes leader.at n=41A007354
- Primes that are palindromic in base 2 (but written here in base 10).at n=27A016041
- Primes that remain prime through 3 iterations of function f(x) = 9x + 2.at n=23A023296
- Primes that remain prime through 4 iterations of function f(x) = 9x + 2.at n=10A023324
- Primes that remain prime through 5 iterations of function f(x) = 9x + 2.at n=4A023352
- Primes with property that when squared all even digits occur together and all odd digits occur together.at n=42A030480
- 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 87.at n=20A031585
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 66 ones.at n=3A031834
- Number of irreducible representations of symmetric group S_n for which every matrix has determinant 1.at n=32A045923
- Primes whose sum of digits is the perfect number 28.at n=14A048517
- a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = a(3) = 1.at n=13A049935
- Fifth term of strong prime quintets: p(m-3)-p(m-4) > p(m-2)-p(m-3) > p(m-1)-p(m-2) > p(m)-p(m-1).at n=20A054812
- Primes of form Sum_{k=1..n} (prime(k)+1).at n=26A062736
- Primes containing 2k digits in which the sum of the first k digits is that of the last k digits.at n=44A068896
- Primes p such that (r-p)/log(p) > 3, where r is the next prime after p.at n=19A082888
- Starting positions of strings of three 9's in the decimal expansion of Pi.at n=5A083642
- a(n) = prime(Pell(n)).at n=8A088747
- Primes which are also prime if their base 19 representation is interpreted as a base 10 number.at n=44A090714
- Primes which are also prime if their base 31 representation is interpreted as a base 10 number.at n=39A090715
- a(n) is the largest prime before A002281(n); repdigits repeating 7.at n=3A099667