230 (number)

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230 (two hundred [and] thirty) is the natural number following 229 and preceding 231.

Additionally, 230 is:

• a composite number, with its divisors being 2, 5, 10, 23, 46, and 115.
• a sphenic number^[1] because it is the product of 3 primes. It is also the first sphenic number to immediately precede another sphenic number.
• palindromic and a repdigit in bases 22 (AA₂₂), 45 (55₄₅), 114 (22₁₁₄), 229 (11₂₂₉)
• a Harshad number in bases 2, 6, 10, 12, 23 (and 16 other bases).
• a happy number.^[2]
• a nontotient^[3] since there is no integer with 230 coprimes below it.
• the sum of the coprime counts for the first 27 integers.
• the aliquot sum of both 454 and 52441.
• part of the 41-aliquot tree.
• the maximal number of pieces that can be obtained by cutting an annulus with 20 cuts.^[4]

The aliquot sequence starting at 224 is: 224, 280, 440, 640, 890, 730, 602, 454, 230, 202, 104, 106, 56, 64, 63, 41, 1, 0.

There are 230 unique space groups describing all possible crystal symmetries.