19961728 has 32 divisors (see below), whose sum is σ = 39981960. Its totient is φ = 9927168.

The previous prime is 19961719. The next prime is 19961729. The reversal of 19961728 is 82716991.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19961729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35175 + ... + 35737.

Almost surely, 2^19961728 is an apocalyptic number.

It is an amenable number.

19961728 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

19961728 is an equidigital number, since it uses as much as digits as its factorization.

19961728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 854 (or 842 counting only the distinct ones).

The product of its digits is 54432, while the sum is 43.

The square root of 19961728 is about 4467.8549663121. The cubic root of 19961728 is about 271.2685074477.

The spelling of 19961728 in words is "nineteen million, nine hundred sixty-one thousand, seven hundred twenty-eight".