28443999 has 4 divisors (see below), whose sum is σ = 37925336. Its totient is φ = 18962664.

The previous prime is 28443997. The next prime is 28444001. The reversal of 28443999 is 99934482.

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

It is an interprime number because it is at equal distance from previous prime (28443997) and next prime (28444001).

It is not a de Polignac number, because 28443999 - 2¹ = 28443997 is a prime.

It is a super-2 number, since 2×28443999² = 1618122158224002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28443991) 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, 4740664 + ... + 4740669.

It is an arithmetic number, because the mean of its divisors is an integer number (9481334).

Almost surely, 2^28443999 is an apocalyptic number.

28443999 is a deficient number, since it is larger than the sum of its proper divisors (9481337).

28443999 is an equidigital number, since it uses as much as digits as its factorization.

28443999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9481336.

The product of its digits is 559872, while the sum is 48.

The square root of 28443999 is about 5333.2915727532. The cubic root of 28443999 is about 305.2555378811.

The spelling of 28443999 in words is "twenty-eight million, four hundred forty-three thousand, nine hundred ninety-nine".