8779
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 31
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 8780
- 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
- 8778
- Möbius Function
- -1
- Radical
- 8779
- 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
- 140
- 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
- 1094
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Irregular table read by rows: row n lists prime factors of 10^n + 1, with multiplicity.at n=28A001271
- Largest prime factor of 10^n + 1.at n=11A003021
- Values of k at which the period of the continued fraction for sqrt(k) sets a new record.at n=47A013645
- a(n) = n*(n-1) + (n-2)*(n-3) + ... + 1*0 + 1 for n odd; otherwise, a(n) = n*(n-1) + (n-2)*(n-3) + ... + 2*1.at n=36A014112
- Eight iterations of Reverse and Add are needed to reach a palindrome.at n=28A015988
- a(n) = least m such that if r and s in {1/2, 1/4, 1/6, ..., 1/(2*n)} satisfy r < s, then r < k/m < (k+3)/m < s for some integer k.at n=34A024845
- Divisors of 10^11 + 1.at n=7A027899
- 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 93.at n=11A031591
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 82 ones.at n=1A031850
- Upper prime of a difference of 18 between consecutive primes.at n=35A031937
- a(n) = (9*n^2 + 3*n + 2)/2.at n=44A038764
- Numerators of continued fraction convergents to sqrt(598).at n=5A042146
- Discriminants of imaginary quadratic fields with class number 15 (negated).at n=33A046012
- Triangle of prime numbers in which n-th row lists all primes p such that 1/p has decimal period n, n >= 1.at n=37A046107
- Primes of the form k(k+1)/2+1 (i.e., central polygonal numbers, or one more than triangular numbers).at n=36A055469
- Primes congruent to 3 modulo 4 generated recursively: a(n) = Min_{p, prime; p mod 4 = 3; p|4Q-1}, where Q is the product of all previous terms in the sequence. The initial term is 3.at n=5A057205
- Greatest prime number p(n) with decimal fraction period of length n.at n=21A061075
- Primes with 11 as smallest positive primitive root.at n=36A061324
- Numbers which need eight 'Reverse and Add' steps to reach a palindrome.at n=23A065213
- Primes of the form floor((8/7)^k).at n=13A067909