28589521 has 4 divisors (see below), whose sum is σ = 28601344. Its totient is φ = 28577700.

The previous prime is 28589513. The next prime is 28589527. The reversal of 28589521 is 12598582.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12598582 = 2 ⋅6299291.

It is a cyclic number.

It is not a de Polignac number, because 28589521 - 2³ = 28589513 is a prime.

It is a super-2 number, since 2×28589521² = 1634721422018882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28589527) 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, 825 + ... + 7606.

It is an arithmetic number, because the mean of its divisors is an integer number (7150336).

Almost surely, 2^28589521 is an apocalyptic number.

It is an amenable number.

28589521 is a deficient number, since it is larger than the sum of its proper divisors (11823).

28589521 is an equidigital number, since it uses as much as digits as its factorization.

28589521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11822.

The product of its digits is 57600, while the sum is 40.

The square root of 28589521 is about 5346.9169621381. The cubic root of 28589521 is about 305.7752240239.

The spelling of 28589521 in words is "twenty-eight million, five hundred eighty-nine thousand, five hundred twenty-one".