28957889 has 4 divisors (see below), whose sum is σ = 28991424. Its totient is φ = 28924356.

The previous prime is 28957879. The next prime is 28957891. The reversal of 28957889 is 98875982.

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 28957889 - 2²⁰ = 27909313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28957879) 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, 15437 + ... + 17210.

It is an arithmetic number, because the mean of its divisors is an integer number (7247856).

Almost surely, 2^28957889 is an apocalyptic number.

It is an amenable number.

28957889 is a deficient number, since it is larger than the sum of its proper divisors (33535).

28957889 is an equidigital number, since it uses as much as digits as its factorization.

28957889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33534.

The product of its digits is 2903040, while the sum is 56.

The square root of 28957889 is about 5381.2534785122. The cubic root of 28957889 is about 307.0828998008.

The spelling of 28957889 in words is "twenty-eight million, nine hundred fifty-seven thousand, eight hundred eighty-nine".