12728105 has 8 divisors (see below), whose sum is σ = 16448712. Its totient is φ = 9399168.

The previous prime is 12728083. The next prime is 12728113. The reversal of 12728105 is 50182721.

It can be written as a sum of positive squares in 4 ways, for example, as 246016 + 12482089 = 496^2 + 3533^2 .

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 12728105 - 2⁶ = 12728041 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 7 ways as a sum of consecutive naturals, for example, 97844 + ... + 97973.

It is an arithmetic number, because the mean of its divisors is an integer number (2056089).

Almost surely, 2^12728105 is an apocalyptic number.

It is an amenable number.

12728105 is a deficient number, since it is larger than the sum of its proper divisors (3720607).

12728105 is a wasteful number, since it uses less digits than its factorization.

12728105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195835.

The product of its (nonzero) digits is 1120, while the sum is 26.

The square root of 12728105 is about 3567.6469836574. The cubic root of 12728105 is about 233.4826334737.

The spelling of 12728105 in words is "twelve million, seven hundred twenty-eight thousand, one hundred five".