1549
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 1550
- 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
- 1548
- Möbius Function
- -1
- Radical
- 1549
- 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
- 122
- 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
- 244
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes p of the form 3k+1 such that -sqrt(p) < sum_{x=1..p} cos(2*Pi*x^3/p) < sqrt(p).at n=36A000922
- Max_{k=0..n} { Number of partitions of n into exactly k parts }.at n=35A002569
- a(n) = 3*a(n-1) + a(n-2), with a(1)=1 and a(2)=4.at n=6A003688
- Number of partitions of n of the form a_1*b_1^2 + a_2*b_2^2 + ...; number of semisimple rings with p^n elements for any prime p.at n=21A004101
- Odd numbers not of form p + 2^k (de Polignac numbers).at n=29A006285
- Primes with both 10 and -10 as primitive root.at n=45A007349
- Coordination sequence T1 for Zeolite Code LAU.at n=28A008124
- Coordination sequence T2 for Zeolite Code LAU.at n=28A008125
- Coordination sequence T3 for Zeolite Code LAU.at n=28A008126
- Coordination sequence T11 for Zeolite Code MFI.at n=25A008163
- Coordination sequence T1 for Zeolite Code ATO.at n=26A008265
- Molien series for A_9.at n=26A008632
- Number of partitions of n into at most 9 parts.at n=26A008638
- Primes p==1 (mod 6) such that 3 and -3 are both cubes (one implies other) modulo p.at n=36A014753
- Numbers k such that the continued fraction for sqrt(k) has period 69.at n=0A020408
- Smallest nonempty set S containing prime divisors of 9k+5 for each k in S.at n=24A020627
- n-th prime p(k) such that p(k) + p(k+4) = p(k+1) + p(k+3).at n=43A022887
- Number of partitions of n into 9 unordered relatively prime parts.at n=26A023029
- Primes p such that 4*p+1 is also prime.at n=44A023212
- Primes p such that 4*p + 7 is also prime.at n=45A023215