28331443 has 4 divisors (see below), whose sum is σ = 32378800. Its totient is φ = 24284088.

The previous prime is 28331437. The next prime is 28331447. The reversal of 28331443 is 34413382.

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

It is a cyclic number.

It is not a de Polignac number, because 28331443 - 2⁵ = 28331411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28331447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2023668 + ... + 2023681.

It is an arithmetic number, because the mean of its divisors is an integer number (8094700).

Almost surely, 2^28331443 is an apocalyptic number.

28331443 is a deficient number, since it is larger than the sum of its proper divisors (4047357).

28331443 is an equidigital number, since it uses as much as digits as its factorization.

28331443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4047356.

The product of its digits is 6912, while the sum is 28.

The square root of 28331443 is about 5322.7289053642. The cubic root of 28331443 is about 304.8523624800.

The spelling of 28331443 in words is "twenty-eight million, three hundred thirty-one thousand, four hundred forty-three".