12128287 has 4 divisors (see below), whose sum is σ = 12135376. Its totient is φ = 12121200.

The previous prime is 12128269. The next prime is 12128329. The reversal of 12128287 is 78282121.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12128287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12128227) by changing a digit.

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, 787 + ... + 4987.

It is an arithmetic number, because the mean of its divisors is an integer number (3033844).

Almost surely, 2^12128287 is an apocalyptic number.

12128287 is a deficient number, since it is larger than the sum of its proper divisors (7089).

12128287 is an equidigital number, since it uses as much as digits as its factorization.

12128287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7088.

The product of its digits is 3584, while the sum is 31.

The square root of 12128287 is about 3482.5690230059. The cubic root of 12128287 is about 229.7558025723.

The spelling of 12128287 in words is "twelve million, one hundred twenty-eight thousand, two hundred eighty-seven".