230 (number)

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

In mathematics

It is a composite number, with its divisors being 2, 5, 10, 23, 46, and 115. Its factorisation makes it a sphenic number. There is no integer with 230 coprimes below it, thus 230 is a nontotient. However, the sum of the coprime counts for the first 27 integers is 230.

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

In base 10, being divisible by the sum of its digits, 230 is a Harshad number.

In other fields

230 is:

• A common voltage in the European Union.
• The year A.D. 230 or 230 BC.
• +230 is the country code for Mauritius.

230 – 239

Two hundred [and] thirty-one has its own article.

Two hundred [and] thirty-two 232 = 2³·29, decagonal number, Mertens function returns 0, noncototient, refactorable number, and telephone number

Two hundred [and] thirty-three 233 prime, Fibonacci number, Sophie Germain prime, Chen prime, Eisenstein prime with no imaginary part, Markov number, self number, sum of 11 consecutive primes (5 + 7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37 + 41), teenage slang for "best friends forever"

Two hundred [and] thirty-four 234 = 2·3²·13, Harshad number, nontotient

Two hundred [and] thirty-five 235 = 5·47, sum of three consecutive primes (73 + 79 + 83), Mertens function returns 0, Number of trees with 11 unlabeled nodes, Smarandache–Wellin number, centered triangular number

U-235 is the fissile isotope of uranium used in the first atomic bombs.

Two hundred [and] thirty-six 236 = 2²·59, Mertens function returns 0, nontotient, happy, sum of twelve consecutive primes (3 + 5 + 7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37 + 41)

Two hundred [and] thirty-seven 237 = 3·79, Blum integer. Room 237 plays a significant role in the Stanley Kubrick film "The Shining"

Two hundred [and] thirty-eight 238 = 2·7·17, sphenic number, sum of the first thirteen primes, Mertens function returns 0, untouchable number.

Two hundred [and] thirty-nine has its own article.