20728120896 has 168 divisors, whose sum is σ = 68602352000. Its totient is φ = 5861154816.

The previous prime is 20728120879. The next prime is 20728120943. The reversal of 20728120896 is 69802182702.

It is a tau number, because it is divible by the number of its divisors (168).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 364605 + ... + 417603.

Almost surely, 2^20728120896 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20728120896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34301176000).

20728120896 is an abundant number, since it is smaller than the sum of its proper divisors (47874231104).

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

20728120896 is a wasteful number, since it uses less digits than its factorization.

20728120896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53121 (or 53108 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The spelling of 20728120896 in words is "twenty billion, seven hundred twenty-eight million, one hundred twenty thousand, eight hundred ninety-six".