1319
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 1320
- 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
- 1318
- Möbius Function
- -1
- Radical
- 1319
- 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
- 145
- 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
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- yes
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 215
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Lesser of twin primes.at n=45A001359
- Smallest prime == 7 (mod 8) where Q(sqrt(-p)) has class number 2n+1.at n=22A002146
- Safe primes p: (p-1)/2 is also prime.at n=29A005385
- Number of esters with n carbon atoms up to stereo-isomerism.at n=8A005958
- Number of line-rooted projective plane trees with n nodes.at n=8A006081
- Worst cases for Pierce expansions (denominators).at n=17A006538
- Primes of form 2n^2 - 2n + 19.at n=21A007639
- Expansion of log(1+sin(x))*cos(x).at n=10A009332
- Expansion of log(1+tanh(x))*cosh(x).at n=10A009389
- Coordination sequence T1 for Zeolite Code WEI.at n=26A009917
- Numbers in which every prefix (in base 10) is 1 or a prime.at n=42A012883
- Number of 8's in all the partitions of n into distinct parts.at n=51A015743
- Number of partitions of n into distinct parts, none being 8.at n=44A015755
- Megaperfect numbers: numbers n where A019294(n) = min {m: n divides sigma^(m) (n)} increases to a record; sigma^(m) means apply the sum-of-divisors function m times.at n=21A019276
- Smallest nonempty set S containing prime divisors of 6k+7 for each k in S.at n=39A020604
- n-th prime p(k) such that p(k) + p(k+9) = p(k+3) + p(k+6).at n=21A022893
- Primes p such that p + 8 is also prime.at n=48A023202
- Primes p such that 4*p + 5 is also prime.at n=48A023214
- Primes p such that 5*p + 4 is also prime.at n=53A023218
- Primes p such that 7*p + 8 is also prime.at n=39A023226