Counting

[GuyBarry]

"813 is a Russian multistyle producer and firefighter, who think of your ears and souls". Not quite sure what that means but you can listen to their music here.

[The Raven]

Indian Airlines Flight 814

Was hijacked on Chrismas Eve 1999 and was forced to land in Kandahar, Afghanistan

[GuyBarry]

The US TV series Lost begins with the crash of Oceanic Airlines Flight 815, leaving the surviving passengers on what seems to be a deserted tropical island.

[DrainBrain]

The Yamaha TX816 is a monster of DX and FM digital synthesis. Apparently.

http://www.vintagesynth.com/yamaha/tx816.php

[GuyBarry]

817 is the 17th centred hexagonal number. You probably don't need telling by now, but that means that 817 dots can be arranged in the shape of a hexagon with one dot in the middle and 16 surrounding layers.

[The Raven]

818 another number that can be read the same upside down

[GuyBarry]

Gallery 819 at New York's Metropolitan Museum of Art houses the later works of Claude Monet.

[DrainBrain]

The Xerox 820 was a computer first produced in 1981, which is also the year I first used a computer.

[GuyBarry]

821 is the first number in a prime quadruplet - a group of four primes of the form {p, p+2, p+6, p+8}. In other words, 821, 823, 827 and 829 are all prime. (This is the first occurrence of a prime quadruplet after p = 191.)

[DrainBrain]

Locomotives 822 and 823 together on the Welshpool and Llanfair Railway.

(Since double posts are not allowed, I assume 823 is still next.)

[GuyBarry]

(Since double posts are not allowed, I assume 823 is still next.)

I'm not sure, but I've got an unusual one for 823 so I'll continue...

The "money bags" hoax email, which has been circulating since 2010, takes the form of a claim that "this year, July [or some other month] has 5 Fridays, 5 Saturdays and 5 Sundays. This happens only once every 823 years". (In fact it happens about once every seven years on average.)

[RobbieM]

824 - The first digit is a product of the second two individually, and also a factor of the second two together. I just spotted that.

[GuyBarry]

United Nations Security Council resolution 825, adopted on 11 May 1993, called on North Korea to reconsider its decision to withdraw from the Nuclear Non-Proliferation Treaty.

[The Orange One]

826 National is a tutoring company based in the USA.

[GuyBarry]

The Short Type 827 was a 1910s British two-seat reconnaissance floatplane.