19728413125 has 10 divisors (see below), whose sum is σ = 24652625822. Its totient is φ = 15782730000.

The previous prime is 19728413099. The next prime is 19728413129. The reversal of 19728413125 is 52131482791.

It can be written as a sum of positive squares in 5 ways, for example, as 13090563396 + 6637849729 = 114414^2 + 81473^2 .

It is not a de Polignac number, because 19728413125 - 2¹³ = 19728404933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19728413129) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 15782106 + ... + 15783355.

Almost surely, 2^19728413125 is an apocalyptic number.

It is an amenable number.

19728413125 is a deficient number, since it is larger than the sum of its proper divisors (4924212697).

19728413125 is an frugal number, since it uses more digits than its factorization.

19728413125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31565481 (or 31565466 counting only the distinct ones).

The product of its digits is 120960, while the sum is 43.

The spelling of 19728413125 in words is "nineteen billion, seven hundred twenty-eight million, four hundred thirteen thousand, one hundred twenty-five".