20289340880 has 80 divisors (see below), whose sum is σ = 49975087104. Its totient is φ = 7634135040.

The previous prime is 20289340843. The next prime is 20289340901. The reversal of 20289340880 is 8804398202.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3684209 + ... + 3689711.

Almost surely, 2^20289340880 is an apocalyptic number.

20289340880 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 20289340880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24987543552).

20289340880 is an abundant number, since it is smaller than the sum of its proper divisors (29685746224).

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

20289340880 is a wasteful number, since it uses less digits than its factorization.

20289340880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8244 (or 8238 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 44.

The spelling of 20289340880 in words is "twenty billion, two hundred eighty-nine million, three hundred forty thousand, eight hundred eighty".