28401 has 4 divisors (see below), whose sum is σ = 37872. Its totient is φ = 18932.

The previous prime is 28393. The next prime is 28403. The reversal of 28401 is 10482.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28401 - 2³ = 28393 is a prime.

It is an Ulam number.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (28403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4731 + ... + 4736.

It is an arithmetic number, because the mean of its divisors is an integer number (9468).

2²⁸⁴⁰¹ is an apocalyptic number.

It is an amenable number.

28401 is a deficient number, since it is larger than the sum of its proper divisors (9471).

28401 is an equidigital number, since it uses as much as digits as its factorization.

28401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9470.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 28401 is about 168.5259623916. The cubic root of 28401 is about 30.5101641301.

Adding to 28401 its reverse (10482), we get a palindrome (38883).

The spelling of 28401 in words is "twenty-eight thousand, four hundred one".