| ||||
|---|---|---|---|---|
| Cardinal | two hundred ten | |||
| Ordinal | 210th (two hundred tenth) | |||
| Factorization | 2 × 3 × 5 × 7 | |||
| Divisors | 1,2,3,5,6,7,10,14,15,21,30,35,42,70,105, 210 | |||
| Greek numeral | ΣΙ´ | |||
| Roman numeral | CCX,ccx | |||
| Binary | 110100102 | |||
| Ternary | 212103 | |||
| Senary | 5506 | |||
| Octal | 3228 | |||
| Duodecimal | 15612 | |||
| Hexadecimal | D216 | |||
210 (two hundred [and] ten) is thenatural number following209 and preceding211.
210 is anabundant number,[1] and Harshad number. It is the product of the first fourprime numbers (2,3,5, and7), and thus aprimorial,[2] where it is the least common multiple of these four prime numbers. 210 is the first primorial number greater than 2 which is notadjacent to 2 primes (211 is prime, but 209 is not).
It is the sum of eight consecutive prime numbers, between13 and the thirteenth prime number:13 + 17 + 19 + 23 + 29 + 31 + 37 +41 = 210.[3]
It is the 20thtriangular number (following190 and preceding231),[4] apentagonal number (following176 and preceding247),[5] and the second smallest to be both triangular and pentagonal (the first is 1; the third is 40755).[3]
It is also anidoneal number, apentatope number, apronic number, and anuntouchable number. 210 is also the third71-gonal number, preceding418.[3]
210 is indexn = 7 in the number of ways to pair up{1, ..., 2n} so that the sum of each pair isprime; i.e., in{1, ..., 14}.[6][7]
It is the largest numbern where the number of distinct representations ofn as thesum of two primes is at most the number of primes in the interval[n/2,n − 2].[8]
