12128785 has 16 divisors (see below), whose sum is σ = 15242256. Its totient is φ = 9255168.

The previous prime is 12128777. The next prime is 12128801. The reversal of 12128785 is 58782121.

It can be written as a sum of positive squares in 8 ways, for example, as 1882384 + 10246401 = 1372^2 + 3201^2 .

It is a cyclic number.

It is not a de Polignac number, because 12128785 - 2³ = 12128777 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12128785.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9187 + ... + 10423.

It is an arithmetic number, because the mean of its divisors is an integer number (952641).

Almost surely, 2^12128785 is an apocalyptic number.

It is an amenable number.

12128785 is a deficient number, since it is larger than the sum of its proper divisors (3113471).

12128785 is a wasteful number, since it uses less digits than its factorization.

12128785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1332.

The product of its digits is 8960, while the sum is 34.

The square root of 12128785 is about 3482.6405212138. The cubic root of 12128785 is about 229.7589471995.

The spelling of 12128785 in words is "twelve million, one hundred twenty-eight thousand, seven hundred eighty-five".