12720728 has 16 divisors (see below), whose sum is σ = 25107000. Its totient is φ = 6025536.

The previous prime is 12720713. The next prime is 12720737. The reversal of 12720728 is 82702721.

It is a self number, because there is not a number n which added to its sum of digits gives 12720728.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41693 + ... + 41996.

Almost surely, 2^12720728 is an apocalyptic number.

It is an amenable number.

12720728 is a deficient number, since it is larger than the sum of its proper divisors (12386272).

12720728 is a wasteful number, since it uses less digits than its factorization.

12720728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83714 (or 83710 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 29.

The square root of 12720728 is about 3566.6129590972. The cubic root of 12720728 is about 233.4375171936.

The spelling of 12720728 in words is "twelve million, seven hundred twenty thousand, seven hundred twenty-eight".