169 (number)

← 168 169 170 →
← 160 161 162 163 164 165 166 167 168 169 → List of numbers — Integers ← 0 100 200 300 400 500 600 700 800 900 →
Cardinal	one hundred sixty-nine
Ordinal	169th (one hundred sixty-ninth)
Factorization	132
Divisors	1, 13, 169
Roman numeral	CLXIX
Binary	101010012
Ternary	200213
Quaternary	22214
Quinary	11345
Senary	4416
Octal	2518
Duodecimal	12112
Hexadecimal	A916
Vigesimal	8920
Base 36	4P36

169 (one hundred [and] sixty-nine) is the natural number following 168 and preceding 170.

169 is an odd number, a composite number, and a deficient number.

169 is a square number: 13 x 13 = 169, and if each number is reversed the equation is still true: 31 x 31 = 961. 144 shares this property: 12 x 12 = 144, 21 x 21 = 441.

169 is one of the few squares to also be a centered hexagonal number. Like all odd squares, it is a centered octagonal number. 169 is an odd-indexed Pell number, thus it is also a Markov number, appearing in the solutions (2, 169, 985), (2, 29, 169), (29, 169, 14701), etc. 169 is the sum of seven consecutive primes: 13 + 17 + 19 + 23 + 29 + 31 + 37. 169 is a difference in consecutive cubes, equaling ${\displaystyle 8^{3}-7^{3}.}$

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