12728915 has 4 divisors (see below), whose sum is σ = 15274704. Its totient is φ = 10183128.

The previous prime is 12728893. The next prime is 12728923. The reversal of 12728915 is 51982721.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12728915 is a prime.

It is a Duffinian number.

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, 1272887 + ... + 1272896.

It is an arithmetic number, because the mean of its divisors is an integer number (3818676).

Almost surely, 2^12728915 is an apocalyptic number.

12728915 is a deficient number, since it is larger than the sum of its proper divisors (2545789).

12728915 is an equidigital number, since it uses as much as digits as its factorization.

12728915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2545788.

The product of its digits is 10080, while the sum is 35.

The square root of 12728915 is about 3567.7605020517. The cubic root of 12728915 is about 233.4875862121.

The spelling of 12728915 in words is "twelve million, seven hundred twenty-eight thousand, nine hundred fifteen".