28538591 has 4 divisors (see below), whose sum is σ = 28557000. Its totient is φ = 28520184.

The previous prime is 28538579. The next prime is 28538593. The reversal of 28538591 is 19583582.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28538591 - 2⁶ = 28538527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28538593) 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, 6641 + ... + 10058.

It is an arithmetic number, because the mean of its divisors is an integer number (7139250).

Almost surely, 2^28538591 is an apocalyptic number.

28538591 is a deficient number, since it is larger than the sum of its proper divisors (18409).

28538591 is a wasteful number, since it uses less digits than its factorization.

28538591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18408.

The product of its digits is 86400, while the sum is 41.

The square root of 28538591 is about 5342.1522816183. The cubic root of 28538591 is about 305.5935445341.

The spelling of 28538591 in words is "twenty-eight million, five hundred thirty-eight thousand, five hundred ninety-one".