28368257 has 4 divisors (see below), whose sum is σ = 30036996. Its totient is φ = 26699520.

The previous prime is 28368253. The next prime is 28368283. The reversal of 28368257 is 75286382.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75286382 = 2 ⋅37643191.

It can be written as a sum of positive squares in 2 ways, for example, as 15437041 + 12931216 = 3929^2 + 3596^2 .

It is not a de Polignac number, because 28368257 - 2² = 28368253 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28368251) 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, 834344 + ... + 834377.

It is an arithmetic number, because the mean of its divisors is an integer number (7509249).

Almost surely, 2^28368257 is an apocalyptic number.

It is an amenable number.

28368257 is a deficient number, since it is larger than the sum of its proper divisors (1668739).

28368257 is a wasteful number, since it uses less digits than its factorization.

28368257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1668738.

The product of its digits is 161280, while the sum is 41.

The square root of 28368257 is about 5326.1859712181. The cubic root of 28368257 is about 304.9843474902.

The spelling of 28368257 in words is "twenty-eight million, three hundred sixty-eight thousand, two hundred fifty-seven".