In number theory, a colossally abundant number (sometimes abbreviated as CA) is a natural number that, in a particular, rigorous sense, has many divisors...

the natural number following 11 and preceding 13. Twelve is the 3rd superior highly composite number, the 3rd colossally abundant number, the 5th highly...

divisor number 1,441,440 = 11th colossally abundant number, 11th superior highly composite number, 40th highly composite number 1,441,889 = Markov number 1...

number, the 19th highly composite number, an abundant number, the 8th colossally abundant number and the number of permutations of 4 items out of 10 choices...

highly composite number, the 4th colossally abundant number, the 9th highly composite number, a unitary perfect number, and an abundant number. It is the smallest...

10th superior highly composite number; 10th colossally abundant number; 38th highly composite number, smallest number divisible by the numbers from 1...

In number theory, a highly abundant number is a natural number with the property that the sum of its divisors (including itself) is greater than the sum...

even prime number, and the first Ramanujan prime. It is also the first superior highly composite number, and the first colossally abundant number. A digon...

primitive abundant number is an abundant number whose proper divisors are all deficient numbers. For example, 20 is a primitive abundant number because:...

number 225,331,713 = self-descriptive number in base 9 229,345,007 = 475 232,792,560 = superior highly composite number; colossally abundant number;...

composite number, the 2nd colossally abundant number, the 3rd triangular number, the 4th highly composite number, a pronic number, a congruent number, a harmonic...

In number theory, an abundant number or excessive number is a positive integer for which the sum of its proper divisors is greater than the number. The...

10, and 12; colossally abundant number; Harshad number in several bases. It is also the highest number with more divisors than any number less than double...

= 15th colossally abundant number, 15th superior highly composite number, and the largest number to be both. 7,007,009,909 = smallest number in base...

5th colossally abundant number. It is also a sparsely totient number. 120 is also the smallest highly composite number with no adjacent prime number, being...

= 3-smooth number 55440 = the 9th superior highly composite number; the 9th colossally abundant number, the 28th highly composite number. 55459 = one...

superior highly composite number. the 7th colossally abundant number. the 18th highly composite number. the last highly composite number that is half of the...

531,778 = Markov number 21,621,600 = 13th colossally abundant number, 13th superior highly composite number 22,222,222 = repdigit 22,235,661 = 33×77 22...

superior highly composite number, the 6th colossally abundant number, a refactorable number, a 5-smooth number, and a Harshad number in decimal since the sum...

also the first 15 colossally abundant numbers, which meet a similar condition based on the sum-of-divisors function rather than the number of divisors. Neither...

The first 15 superabundant numbers are the same as the first 15 colossally abundant numbers. In decimal, 15 contains the digits 1 and 5 and is the result...

month, the number of pairs of rabbits is equal to the number of mature pairs (that is, the number of pairs in month n – 2) plus the number of pairs alive...

A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that...

A composite number is a positive integer that can be formed by multiplying two smaller positive integers. Accordingly it is a positive integer that has...

semiperfect number is 945 (see, e.g., Friedman 1993). A semiperfect number is necessarily either perfect or abundant. An abundant number that is not semiperfect...

the number 1 differently than larger numbers, sometimes even not as a number at all. Euclid, for example, defined a unit first and then a number as a...

In number theory, an n-smooth (or n-friable) number is an integer whose prime factors are all less than or equal to n. For example, a 7-smooth number is...

perfect number. Most abundant numbers are also semiperfect; abundant numbers which are not semiperfect are called weird numbers. Hyperperfect number Leinster...

In number theory, a Carmichael number is a composite number ⁠ n {\displaystyle n} ⁠ which in modular arithmetic satisfies the congruence relation: b n...

In mathematics, a harshad number (or Niven number) in a given number base is an integer that is divisible by the sum of its digits when written in that...