170 (NUMBER)

'170' is the natural number following 169 and preceding 171.

Cardinal	One hundred [and] seventy
Ordinal	170th
Factorization	$2\; cdot\; 5\; cdot\; 17$
Roman numeral	CLXX
Binary	10101010
Hexadecimal	AA

'One hundred [and] seventy' is a sphenic number. It is the smallest n for which φ(n) and σ(n) are both square. But 170 is never a solution for φ(x), making it a nontotient. Nor is it ever a solution to x - φ(x), making it a noncototient. 170 is a repdigit in base 4 (2222).
'One hundred [and] seventy' is also

★ The year AD '170' or 170 BC.

★ The largest number that Google's built-in calculator function will compute the factorial of.