28389591 has 12 divisors (see below), whose sum is σ = 43165720. Its totient is φ = 17930160.

The previous prime is 28389533. The next prime is 28389601. The reversal of 28389591 is 19598382.

It is a happy number.

28389591 is a `hidden beast` number, since 28 + 38 + 9 + 591 = 666.

It is not a de Polignac number, because 28389591 - 2⁶ = 28389527 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28389511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 82840 + ... + 83181.

Almost surely, 2^28389591 is an apocalyptic number.

28389591 is a deficient number, since it is larger than the sum of its proper divisors (14776129).

28389591 is a wasteful number, since it uses less digits than its factorization.

28389591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166046 (or 166043 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The square root of 28389591 is about 5328.1883412657. The cubic root of 28389591 is about 305.0607815799.

The spelling of 28389591 in words is "twenty-eight million, three hundred eighty-nine thousand, five hundred ninety-one".