28288349 has 4 divisors (see below), whose sum is σ = 28341180. Its totient is φ = 28235520.

The previous prime is 28288331. The next prime is 28288363. The reversal of 28288349 is 94388282.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11682724 + 16605625 = 3418^2 + 4075^2 .

It is a cyclic number.

It is not a de Polignac number, because 28288349 - 2¹² = 28284253 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 (28284349) 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, 25604 + ... + 26685.

It is an arithmetic number, because the mean of its divisors is an integer number (7085295).

Almost surely, 2^28288349 is an apocalyptic number.

It is an amenable number.

28288349 is a deficient number, since it is larger than the sum of its proper divisors (52831).

28288349 is an equidigital number, since it uses as much as digits as its factorization.

28288349 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52830.

The product of its digits is 221184, while the sum is 44.

The square root of 28288349 is about 5318.6792533485. The cubic root of 28288349 is about 304.6977171713.

The spelling of 28288349 in words is "twenty-eight million, two hundred eighty-eight thousand, three hundred forty-nine".