たりとも and として+ない

This page explains 2 negative literary expressions that mean “Not even 1”:

• たりとも – Not even one
• として + ない – Not even one/Only one

See also だに

たりとも

Not Even One
1 + counter + たりとも + Negative

たりとも + Negative means “Not even one”. It is a strong emphasizing statement.
Its somewhat common in anime, so you’ve probably heard it before.
も + ない tends to be used in daily conversation instead.

It must be used with the number 1, but not necessarily the smallest unit.
I.E. 1 second, 1 minute, 1 hour are all acceptable as long as they are “small” for the situation.

Frequently used with time words and 一滴 (One drop)
Frequently used with 無駄に(は)できない

May be used with “must not” “Should not” type statements.

Examples

• 一秒たりとも無駄にできない
  Can’t waste even a second.
  
  
• 一滴たりとも溢してはいけない
  Must not spill even a single drop.
  
  
• 彼女のことを一日たりとも忘れたことがない
  I haven’t forgotten about her for even a day.
  
  
• 一匹たりとも逃がさない
  I won’t let even a single one escape.
  
  

として + ない

Not Even One/Only One
1 + counter + として + Negative
2 + counter + として + Negative

として + ない is a little bit rarer than たりとも + ない, but has the same meaning.
Like たりとも it is usually replaced by も + ない in everyday speech. 

Unlike たりとも, it may be used with 2 in rare cases. (In which case it means 1 instead of 0)
When used with 2, it means 1しかいない

として+ない usually only uses simple negative verbs or ない/いない.

Used with 一人 more commonly than たりとも

Examples

• 最低賃金では、応募してくる人は一人としていない
  At minimum wage, there’s not even one person who came applying.
  
  
• こんなことができるのは、この世に二人としていない
  There’s not two people in this world who could do that. (Only 1 person)
  
  
• 一分として無駄にはできない
  Can’t waste even a minute.
  
  

Expressions

• 何人たりともいない*
  Not even one person/anyone
  
  
• 誰一人としていない
  Not even a single person
  
  
• 何一つとしてない
  Not even a single thing
  
  
• どれ一つとしてもない
  Not even a single one.

*何人 (なんぴと) is a rare word basically only used in this expression.