28442 has 4 divisors (see below), whose sum is σ = 42666. Its totient is φ = 14220.

The previous prime is 28439. The next prime is 28447. The reversal of 28442 is 24482.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24482 = 2 ⋅12241.

It can be written as a sum of positive squares in only one way, i.e., 22201 + 6241 = 149^2 + 79^2 .

It is a pancake number, because a pancake can be divided into 28442 parts by 238 straight cuts.

It is a nialpdrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 28442.

It is not an unprimeable number, because it can be changed into a prime (28447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7109 + ... + 7112.

2²⁸⁴⁴² is an apocalyptic number.

28442 is a deficient number, since it is larger than the sum of its proper divisors (14224).

28442 is a wasteful number, since it uses less digits than its factorization.

28442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14223.

The product of its digits is 512, while the sum is 20.

The square root of 28442 is about 168.6475615003. The cubic root of 28442 is about 30.5248386752.

The spelling of 28442 in words is "twenty-eight thousand, four hundred forty-two".