28239887 has 8 divisors (see below), whose sum is σ = 30453696. Its totient is φ = 26032032.

The previous prime is 28239877. The next prime is 28239899. The reversal of 28239887 is 78893282.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28239887 - 2¹⁰ = 28238863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28239817) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16433 + ... + 18069.

It is an arithmetic number, because the mean of its divisors is an integer number (3806712).

Almost surely, 2^28239887 is an apocalyptic number.

28239887 is a deficient number, since it is larger than the sum of its proper divisors (2213809).

28239887 is a wasteful number, since it uses less digits than its factorization.

28239887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2977.

The product of its digits is 387072, while the sum is 47.

The square root of 28239887 is about 5314.1214701962. The cubic root of 28239887 is about 304.5236207492.

The spelling of 28239887 in words is "twenty-eight million, two hundred thirty-nine thousand, eight hundred eighty-seven".