In Mathematics
- 195 is an odd number
- 195 is a composite number
- 195 is a deficient number, as 141 is less than 195
- 195 is a Harshad number
- 195 is a lucky number
- 195 is a sphenic number, in the middle of the prime quadruplet 191, 193, 197 and 199
- 195 is a square-free number
- 195 is the sum of eleven consecutive primes: 3 + 5 + 7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37
- Although not itself prime, 195 passes through Ulam's sieve and thus is a lucky number
- Divisors of 195: 1, 3, 5, 13, 15, 39, 65, 195
- 195 is the smallest number expressed as a sum of distinct squares in 16 different ways (sequence A097563 in OEIS)
- 195 is both a 21-gonal and 66-gonal number
Read more about this topic: 195 (number)
Famous quotes containing the word mathematics:
“In mathematics he was greater
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The clock doth strike, by algebra.”
—Samuel Butler (1612–1680)