138

Names of 138

• Cardinal: 138 can be written as One hundred thirty-eight.

Scientific notation

• Scientific notation: 1.38 × 10²

Factors of 138

• Number of distinct prime factors ω(n): 3
• Total number of prime factors Ω(n): 3
• Sum of prime factors: 28

Divisors of 138

• Number of divisors d(n): 8
• Complete list of divisors:
  1 2 3 6 23 46 69 138
• Sum of all divisors σ(n): 288
• Sum of proper divisors (its aliquot sum) s(n): 150
• 138 is an abundant number, because the sum of its proper divisors (150) is greater than itself. Its abundance is 12

Bases of 138

• Binary: 10001010₂
• Hexadecimal: 0x8A
• Base-36: 3U

Squares and roots of 138

• 138 squared (138²) is 19044
• 138 cubed (138³) is 2628072
• The square root of 138 is 11.7473401245
• The cube root of 138 is 5.1676492525

Scales and comparisons

• 138 seconds is equal to 2 minutes, 18 seconds.
• To count from 1 to 138 would take you about nine seconds.

  This is a very rough estimate, based on a speaking rate of half a second every third order of magnitude. If you speak quickly, you could probably say any randomly-chosen number between one and a thousand in around half a second. Very big numbers obviously take longer to say, so we add half a second for every extra x1000. (We do not count involuntary pauses, bathroom breaks or the necessity of sleep in our calculation!)

• A cube with a volume of 138 cubic inches would be around 0.4 feet tall.

Recreational maths with 138

• 138 backwards is 831
• The number of decimal digits it has is: 3
• The sum of 138's digits is 12
• More coming soon!