428
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 756
- Proper Divisor Sum (Aliquot Sum)
- 328
- 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
- 212
- Möbius Function
- 0
- Radical
- 214
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 2
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
- 102
- Smith Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Names
- German
- vierhundertachtundzwanzig· ordinal: vierhundertachtundzwanzigste
- English
- four hundred twenty-eight· ordinal: four hundred twenty-eighth
- Spanish
- cuatrocientos veintiocho· ordinal: 428º
- French
- quatre cent vingt-huit· ordinal: quatre cent vingt-huitième
- Italian
- quattrocentoventotto· ordinal: 428º
- Latin
- quadringenti viginti octo· ordinal: 428.
- Portuguese
- quatrocentos e vinte e oito· ordinal: 428º
Appears in sequences
- Number of ways to pair up {1^2, 2^2, ..., (2n)^2 } so sum of each pair is prime.at n=8A000348
- Related to population of numbers of form x^2 + y^2.at n=10A000709
- Numbers beginning with letter 'f' in English.at n=52A000867
- Number of ways of making change for n cents using coins of 1, 2, 5, 10, 25, 50 cents.at n=51A001302
- Number of graphs with n nodes and n-2 edges.at n=9A001430
- Catalan numbers - 1.at n=5A001453
- Primes multiplied by 4.at n=27A001749
- Numbers k such that binomial(2*k,k) is divisible by (k+1)^2.at n=36A002503
- a(n) = Sum_{d|n, d <= 3} d^2 + 3*Sum_{d|n, d>3} d.at n=65A002660
- a(n) = Sum_{k|n} mu(k)*Catalan(n/k) (mu = Moebius function A008683).at n=6A002996
- Number of atoms in a decahedron with n shells.at n=8A004068
- a(n) = n^2 + prime(n).at n=18A004232
- Divisible only by primes congruent to 2 mod 7.at n=35A004620
- Expansion of x*(1+x-x^2)/((1-x)^4*(1+x)).at n=15A005744
- Weighted count of partitions with odd parts.at n=23A005896
- a(n) = floor(tau*a(n-1)) + floor(tau*a(n-2)) with a(0)=0 and a(1)=2.at n=8A005909
- Numbers n such that n^32 + 1 is prime.at n=12A006315
- Number of polyhedral graphs with n nodes and minimal degree 4.at n=7A007025
- Let P(n) of a sequence s(1),s(2),s(3),... be obtained by leaving s(1),...,s(n) fixed and reversing every n consecutive terms thereafter; apply P(2) to 1,2,3,... to get PS(2), then apply P(3) to PS(2) to get PS(3), then apply P(4) to PS(3), etc. This sequence is the limit of PS(n).at n=42A007062
- Next term is uniquely the sum of 3 earlier terms.at n=32A007087