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169 (number)

169 is the natural number following one hundred sixty-eight and preceding one hundred seventy.

169
Cardinal one hundred [and]
sixty-nine
Ordinal169th
Factorization169 = 132
Roman numeralCLXIX
Binary10101001
HexadecimalA9

One hundred sixty-nine is one of the few squares to also be a centered hexagonal number. But like any other odd square, it is also a centered octagonal number.

It is a Pell number.

It is the sum of seven consecutive primes, 13 + 17 + 19 + 23 + 29 + 31 + 37.

It is the number of nonequivalent starting hands in Texas hold 'em (see http://www.math.sfu.ca/~alspach/art3.pdf for an explanation).

See also one hundred sixty

For the year AD, see 169 AD.

01-04-2007 01:18:14
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