20609728128 has 576 divisors, whose sum is σ = 70826857920. Its totient is φ = 5912248320.

The previous prime is 20609728003. The next prime is 20609728157. The reversal of 20609728128 is 82182790602.

20609728128 is a `hidden beast` number, since 2 + 0 + 609 + 7 + 28 + 12 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 212471376 + ... + 212471472.

It is an arithmetic number, because the mean of its divisors is an integer number (122963295).

Almost surely, 2^20609728128 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 20609728128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35413428960).

20609728128 is an abundant number, since it is smaller than the sum of its proper divisors (50217129792).

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

20609728128 is an frugal number, since it uses more digits than its factorization.

20609728128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169 (or 136 counting only the distinct ones).

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

The spelling of 20609728128 in words is "twenty billion, six hundred nine million, seven hundred twenty-eight thousand, one hundred twenty-eight".