19728265 has 8 divisors (see below), whose sum is σ = 24490440. Its totient is φ = 15238272.

The previous prime is 19728259. The next prime is 19728281. The reversal of 19728265 is 56282791.

It can be written as a sum of positive squares in 4 ways, for example, as 200704 + 19527561 = 448^2 + 4419^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19728265 - 2⁹ = 19727753 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67884 + ... + 68173.

It is an arithmetic number, because the mean of its divisors is an integer number (3061305).

Almost surely, 2^19728265 is an apocalyptic number.

It is an amenable number.

19728265 is a deficient number, since it is larger than the sum of its proper divisors (4762175).

19728265 is a wasteful number, since it uses less digits than its factorization.

19728265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136091.

The product of its digits is 60480, while the sum is 40.

The square root of 19728265 is about 4441.6511569460. The cubic root of 19728265 is about 270.2068145662.

The spelling of 19728265 in words is "nineteen million, seven hundred twenty-eight thousand, two hundred sixty-five".