17807
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 17808
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 17806
- Möbius Function
- -1
- Radical
- 17807
- 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
- 97
- 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
- 2043
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Lower prime of a difference of 20 between consecutive primes.at n=34A031938
- Triangle read by rows. Same rule as Aitken triangle (A011971) except T(0,0) = 1, T(1,0) = 2.at n=41A046937
- Sequence formed from rows of triangle A046937.at n=34A046938
- Expansion of (1-x)/(1+x^2+x^3).at n=57A078032
- Expansion of (1-x)/(1+2*x+x^2-x^3).at n=26A078064
- Primes p such that primorial(p)/2 - 2 is prime.at n=26A096547
- Primes of the form a^5 + b^3 with a,b>0.at n=23A100273
- Numbers k such that k^2 divides 3^k - 2^k - 1.at n=8A127074
- Primes p such that p^2 divides 3^p - 2^p - 1; or primes in A127074.at n=5A130060
- Prime numbers, isolated from neighboring primes by >14.at n=28A137874
- Primes of the form 41+(n+n^2)/2=41+A000217(n).at n=24A139219
- Running prime totals of prime factors (without multiplicity) of consecutive composite N.at n=41A140610
- Primes congruent to 52 mod 53.at n=40A142582
- Primes congruent to 48 mod 59.at n=40A142775
- Primes congruent to 56 mod 61.at n=34A142854
- Number of nX(n+5) binary matrices with rows and columns each in strictly increasing order as binary numbers and every 0 adjacent to a 1 and every 1 adjacent to a 0.at n=7A181016
- Primes p that become composite when any nonzero decimal digit is appended or deleted on the right or left of p.at n=36A226144
- Primes p such that (2^p+1)^(p-1) == 1 (mod p^2).at n=4A260507
- Primes p such that p=prime(k), prime(k+1), and prime(k+2) end in the same digit.at n=13A328452
- Number of minimal dominating sets in the n-dipyramidal graph (for n > 3).at n=28A347638