1423
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 1424
- 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
- 1422
- Möbius Function
- -1
- Radical
- 1423
- 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
- 65
- 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
- 224
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes that divide at least one term in every Fibonacci sequence.at n=46A000057
- Number of primes < prime(n)^2.at n=28A000879
- Primes p such that the multiplicative order of 2 modulo p is (p-1)/6.at n=9A001136
- Let p be the n-th odd prime. a(n) is the least prime congruent to 7 modulo 8 such that Legendre(-a(n), q) = -Legendre(-1, q) for all odd primes q <= p.at n=6A001988
- Largest prime == 7 (mod 8) with class number 2n+1.at n=4A002147
- Numerators of coefficients of log(1+x)/sqrt(1+x).at n=7A002549
- a(n) = round(n*phi^7), where phi is the golden ratio, A001622.at n=49A004942
- a(n) = ceiling(n*phi^7), where phi is the golden ratio, A001622.at n=49A004962
- Prime triples: p; p+2 or p+4; p+6 all prime.at n=35A007529
- Primes of form n^2 + n + 17.at n=29A007635
- Primes of form 2n^2 - 2n + 19.at n=22A007639
- Coordination sequence T2 for Zeolite Code AET.at n=26A008008
- Dates of birth of Kings Louis I, II, ... of France.at n=10A008746
- Coordination sequence T2 for Keatite.at n=21A009845
- a(0) = 1, a(n) = 29*n^2 + 2 for n>0.at n=7A010019
- a(n) = floor( n*(n-1)*(n-2)/23 ).at n=33A011905
- Primes of the form x^2 + 27y^2.at n=30A014752
- Numbers n such that phi(n + 9) | sigma(n) for n not congruent to 0 (mod 3).at n=28A015849
- Numbers k such that sigma(k) + 4 = sigma(k+4).at n=48A015913
- Numbers k=3*m+1 such that 2^m == 1 (mod k).at n=31A016108