2617
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2618
- 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
- 2616
- Möbius Function
- -1
- Radical
- 2617
- 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
- 84
- 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
- 380
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Let A(n) = #{(i,j): i^2 + j^2 <= n}, V(n) = Pi*n, P(n) = A(n) - V(n); A000099 gives values of n where |P(n)| sets a new record; sequence gives A(A000099(n)).at n=19A000323
- Wagstaff numbers: numbers k such that (2^k + 1)/3 is prime.at n=21A000978
- Record values in A005210.at n=54A005211
- Prime self (or Colombian) numbers: primes not expressible as the sum of an integer and its digit sum.at n=40A006378
- From relations between Siegel theta series.at n=30A006476
- Coordination sequence T2 for Zeolite Code PHI.at n=37A008228
- Coordination sequence T1 for Zeolite Code SAO.at n=40A019571
- Numbers k such that the continued fraction for sqrt(k) has period 49.at n=2A020388
- Smallest nonempty set S containing prime divisors of 5k+2 for each k in S.at n=31A020596
- Smallest nonempty set S containing prime divisors of 10k+4 for each k in S.at n=32A020634
- a(n) = a(n-1) + a(n-2) + 1, with a(0) = 1 and a(1) = 9.at n=13A022323
- Primes that remain prime through 2 iterations of function f(x) = 2x + 3.at n=39A023242
- Primes that remain prime through 2 iterations of the function f(x) = 3*x + 2.at n=29A023246
- Primes that remain prime through 2 iterations of function f(x) = 9x + 8.at n=37A023267
- Primes that remain prime through 3 iterations of function f(x) = 9x + 8.at n=10A023298
- Discriminants of quintic fields with 4 complex conjugates.at n=5A023685
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (Fibonacci numbers), t = A001950 (upper Wythoff sequence).at n=17A024465
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (Fibonacci numbers), t = A001950 (upper Wythoff sequence).at n=17A025085
- Primes that are palindromic in base 14.at n=27A029981
- Primes with property that when squared all even digits occur together and all odd digits occur together.at n=29A030480