19728032640625 has 21 divisors (see below), whose sum is σ = 24660419166813. Its totient is φ = 15781981950000.

The previous prime is 19728032640583. The next prime is 19728032640643. The reversal of 19728032640625 is 52604623082791.

It is a happy number.

The square root of 19728032640625 is 4441625.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 10 ways, for example, as 5883501401649 + 13844531238976 = 2425593^2 + 3720824^2 .

It is not a de Polignac number, because 19728032640625 - 2¹⁹ = 19728032116337 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 555185359 + ... + 555220891.

It is a 1-persistent number, because it is pandigital, but 2⋅19728032640625 = 39456065281250 is not.

Almost surely, 2^{19728032640625} is an apocalyptic number.

19728032640625 is the 4441625-th square number.

19728032640625 is the 2220813-rd centered octagonal number.

It is an amenable number.

19728032640625 is a deficient number, since it is larger than the sum of its proper divisors (4932386526188).

19728032640625 is an frugal number, since it uses more digits than its factorization.

19728032640625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71096 (or 35538 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 55.

The spelling of 19728032640625 in words is "nineteen trillion, seven hundred twenty-eight billion, thirty-two million, six hundred forty thousand, six hundred twenty-five".