28931015 has 8 divisors (see below), whose sum is σ = 36544560. Its totient is φ = 21926592.

The previous prime is 28930973. The next prime is 28931017. The reversal of 28931015 is 51013982.

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

It is a cyclic number.

It is not a de Polignac number, because 28931015 - 2¹⁰ = 28929991 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28931017) 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, 152174 + ... + 152363.

It is an arithmetic number, because the mean of its divisors is an integer number (4568070).

Almost surely, 2^28931015 is an apocalyptic number.

28931015 is a deficient number, since it is larger than the sum of its proper divisors (7613545).

28931015 is a wasteful number, since it uses less digits than its factorization.

28931015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304561.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 28931015 is about 5378.7558970453. The cubic root of 28931015 is about 306.9878756083.

Adding to 28931015 its reverse (51013982), we get a palindrome (79944997).

The spelling of 28931015 in words is "twenty-eight million, nine hundred thirty-one thousand, fifteen".