19986728 has 16 divisors (see below), whose sum is σ = 37716180. Its totient is φ = 9929088.

The previous prime is 19986691. The next prime is 19986731. The reversal of 19986728 is 82768991.

It can be written as a sum of positive squares in 2 ways, for example, as 19909444 + 77284 = 4462^2 + 278^2 .

It is a super-2 number, since 2×19986728² = 798938592291968, which contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 6701 + ... + 9212.

Almost surely, 2^19986728 is an apocalyptic number.

It is an amenable number.

19986728 is a deficient number, since it is larger than the sum of its proper divisors (17729452).

19986728 is a wasteful number, since it uses less digits than its factorization.

19986728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16076 (or 16072 counting only the distinct ones).

The product of its digits is 435456, while the sum is 50.

The square root of 19986728 is about 4470.6518540365. The cubic root of 19986728 is about 271.3817054554.

The spelling of 19986728 in words is "nineteen million, nine hundred eighty-six thousand, seven hundred twenty-eight".