28289815 has 8 divisors (see below), whose sum is σ = 34196400. Its totient is φ = 22466112.

The previous prime is 28289813. The next prime is 28289827. The reversal of 28289815 is 51898282.

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 28289815 - 2¹ = 28289813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28289813) 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, 19965 + ... + 21334.

It is an arithmetic number, because the mean of its divisors is an integer number (4274550).

Almost surely, 2^28289815 is an apocalyptic number.

28289815 is a deficient number, since it is larger than the sum of its proper divisors (5906585).

28289815 is a wasteful number, since it uses less digits than its factorization.

28289815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41441.

The product of its digits is 92160, while the sum is 43.

The square root of 28289815 is about 5318.8170677323. The cubic root of 28289815 is about 304.7029805766.

The spelling of 28289815 in words is "twenty-eight million, two hundred eighty-nine thousand, eight hundred fifteen".