7927
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7928
- 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
- 7926
- Möbius Function
- -1
- Radical
- 7927
- 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
- 52
- 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
- 1001
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers k such that 13*2^k - 1 is prime.at n=8A001773
- 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 89.at n=1A031587
- Numbers k such that 29*2^k+1 is prime.at n=22A032364
- Numbers having three 7's in base 9.at n=33A043483
- Primes p from A031924 such that A052180(primepi(p)) = 7.at n=42A052231
- Third term of strong prime 5-tuples: p(m-1)-p(m-2) > p(m)-p(m-1) > p(m+1)-p(m) > p(m+2)-p(m+1).at n=22A054810
- Primes of the form k^2+6.at n=10A056909
- Smallest prime > the n-th nontrivial power of a prime.at n=48A060846
- Primes starting and ending with 7.at n=33A062334
- Smallest prime larger than square of n-th prime.at n=23A062772
- Largest eigenvalue, rounded to the nearest integer, of a rank n matrix of 1..n^2 filled successively along rows.at n=24A072333
- Least m such that A078142(m) gives the n-th prime, where A078142(n) is the sum of the differences of the distinct prime factors p of n and the next square larger than p.at n=39A073939
- Numbers k such that prime(k) + prime(k+1) + prime(k+2) is a square.at n=16A076305
- Primes of the form p^2 + 6 where p is prime.at n=6A079141
- a(1) = 2, a(n+1) = smallest prime of the form a(n) + k*prime(n+1), k >1.at n=26A085041
- Primes p such that 6p + 1 and (p-1)/6 are primes.at n=15A085957
- Primes arising as the arithmetic mean of first n terms of A090918.at n=45A090919
- Primes p such that the sum of the digits of p is not prime, but the sum of the cubes of the digits of p is prime.at n=6A091365
- a(1) = 3; for n > 1 a(n) is the least prime of form a(n-1) + k*prime(n-1) with k > 0.at n=27A095184
- Sum of the left diagonal in ordered 3 X 3 prime squares.at n=42A105090