Abundant number information

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...

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

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...

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

whereas an abundant number has a sum of its proper divisors that is larger than the number itself. Primitive abundant numbers are abundant numbers whose...

In number theory, a weird number is a natural number that is abundant but not semiperfect. In other words, the sum of the proper divisors (divisors including...