20109017680 has 80 divisors (see below), whose sum is σ = 47819439360. Its totient is φ = 7860727296.

The previous prime is 20109017651. The next prime is 20109017683. The reversal of 20109017680 is 8671090102.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20109017683) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2775022 + ... + 2782258.

It is an arithmetic number, because the mean of its divisors is an integer number (597742992).

Almost surely, 2^20109017680 is an apocalyptic number.

20109017680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20109017680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23909719680).

20109017680 is an abundant number, since it is smaller than the sum of its proper divisors (27710421680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20109017680 is a wasteful number, since it uses less digits than its factorization.

20109017680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8036 (or 8030 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 34.

The spelling of 20109017680 in words is "twenty billion, one hundred nine million, seventeen thousand, six hundred eighty".