7741
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
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7742
- 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
- 7740
- Möbius Function
- -1
- Radical
- 7741
- 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
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 982
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of trees with n unlabeled nodes.at n=15A000055
- Indices of prime Lucas numbers.at n=31A001606
- Numbers k such that the continued fraction for sqrt(k) has period 99.at n=5A020438
- Primes that remain prime through 3 iterations of function f(x) = 5x + 8.at n=18A023286
- Primes that remain prime through 3 iterations of function f(x) = 10x + 9.at n=26A023301
- Primes that remain prime through 4 iterations of function f(x) = 10x + 9.at n=7A023329
- Number of unlabeled (and unrooted) trees on n nodes having a centroid.at n=15A027416
- Primes of form k^2 - 3.at n=16A028874
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 44 ones.at n=25A031812
- Initial terms of '4-block' primes as described in A032591.at n=15A032592
- Numerators of continued fraction convergents to sqrt(396).at n=4A041752
- Second term of strong prime 5-tuples: p(m)-p(m-1) > p(m+1)-p(m) > p(m+2)-p(m+1) > p(m+3)-p(m+2).at n=20A054809
- 3*Fibonacci(n) - 11.at n=13A054968
- Primes p whose period of reciprocal equals (p-1)/9.at n=6A056214
- Primes such that replacing each digit d with d copies of the digit d produces a prime. Zeros are not allowed.at n=43A057628
- Primes p such that x^43 = 2 has no solution mod p.at n=22A059243
- Numbers k such that floor(phi^k) is prime, where phi is the golden ratio.at n=31A059791
- Primes p such that x^3 = 2 has a solution mod p, but x^(3^2) = 2 has no solution mod p.at n=38A070180
- Primes having only {1, 4, 7} as digits.at n=22A079651
- a(n)*a(n+3) - a(n+1)*a(n+2) = 5, given a(0)=a(1)=1, a(2)=3.at n=9A080874