28442239 has 4 divisors (see below), whose sum is σ = 32505424. Its totient is φ = 24379056.

The previous prime is 28442231. The next prime is 28442273. The reversal of 28442239 is 93224482.

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 28442239 - 2³ = 28442231 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28442231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2031582 + ... + 2031595.

It is an arithmetic number, because the mean of its divisors is an integer number (8126356).

Almost surely, 2^28442239 is an apocalyptic number.

28442239 is a deficient number, since it is larger than the sum of its proper divisors (4063185).

28442239 is an equidigital number, since it uses as much as digits as its factorization.

28442239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4063184.

The product of its digits is 27648, while the sum is 34.

The square root of 28442239 is about 5333.1265689087. The cubic root of 28442239 is about 305.2492417572.

The spelling of 28442239 in words is "twenty-eight million, four hundred forty-two thousand, two hundred thirty-nine".