@MathBabbler
received the following tweet from@MAAnow
on2013.12.11
.Today's number is 689 http://bit.ly/J4wTapHmm... From the MAA posting: "689 is the smallest strobogrammatic brilliant number. Deleting the middle digit gives the smallest strobogrammatic semiprime (69)."
MathBabbler Number Analyst (MBNA) output: ========================================= 689 is a natural, whole, integer 689 is odd 689 proper divisors are: 1,13,53, 689 has 3 proper divisors 689 is deficient (sum of divisors is 67; ratio: 0.0972424) 689 is unhappy 689 is a Squarefree Number 689 is not a Harshad number 689 is not prime 689 has the prime factors: 13*53 (sum=66) 689 is semiprime (biprime or 2-almost prime) 13...53...answer: 66 689 is the sum of 7 consecutive primes 689 = 83 + 89 + 97 + 101 + 103 + 107 + 109 689 in octal is 01261 689 in hexadecimal is 0x2b1 689 in binary is 1010110001 (is odious) 689 nearest square numbers: -13...40 (676...729 [27]) sqrt(689) = 26.2488 ln(689) = 6.53524 log(689) = 2.83822 689 reciprocal is .00145137880986937590711175616835 689! is 1.32556e+1658 689 is 219.316 Pi years 689 is 34 score and 9 years 689 written as a Roman numeral is DCLXXXIX 689 = 345^2 - 344^2 and 345 + 344 = 689
log8(689)
= 3.14279, which when rounded to the nearest hundredth (3.14) equals Pi rounded to the nearest hundredth.Update::2015.12.02
FindTheFactors.com::What Makes 689 Amazing?
Creator: Gerald Thurman
[gthurman@gmail.com]
Created: 11 December 2013