7607
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7608
- 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
- 7606
- Möbius Function
- -1
- Radical
- 7607
- 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
- 83
- 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
- yes
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 967
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Triangle T(n,k) giving number of immersions of the oriented circle into the oriented plane with n double points and index k, k = -n-1, -n+1, ..., n-1, n+1.at n=42A008985
- Triangle T(n,k) giving number of immersions of the oriented circle into the oriented plane with n double points and index k, k = -n-1, -n+1, ..., n-1, n+1.at n=38A008985
- a(0) = 1, a(n) = 5*n^2 + 2 for n>0.at n=39A010001
- Primes that are palindromic in base 2 (but written here in base 10).at n=26A016041
- a(n) = a(n-1) + a(n-2) + 1, with a(0)=3, a(1)=9.at n=15A022408
- a(n) = floor( exp(7/17)*n! ).at n=6A030893
- 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=5A031585
- Lower prime of a pair of consecutive primes having a difference of 14.at n=38A031932
- Numbers k such that 41*2^k+1 is prime.at n=7A032370
- Primes with indices that are primes with prime indices.at n=37A038580
- Main diagonal of Family 1 "Rule 90 x Rule 150" array.at n=3A048709
- Family 1 "Rule 90 x Rule 150 Array" read by antidiagonals.at n=24A048710
- a(n) = Xpower(n,3).at n=27A048732
- Primes prime(k) for which A049076(k) = 3.at n=25A049079
- Least prime in A031932 (lesser of 14-twins) whose distance to the next 14-twin is 6*n.at n=13A052356
- Numbers d such that, for some k, the upper and lower primes closest to k! are k! + d and k! - d.at n=8A053711
- Primes p such that p^8 reversed is also prime.at n=38A059701
- Primes starting and ending with 7.at n=24A062334
- Primes p such that (p-1)/2 and (p-3)/4 are also prime.at n=18A066179
- a(0) = 2; a(n) for n > 0 is the smallest prime greater than a(n-1) that differs from a(n-1) by a square.at n=32A073609