28238449 has 4 divisors (see below), whose sum is σ = 28275940. Its totient is φ = 28200960.

The previous prime is 28238447. The next prime is 28238519. The reversal of 28238449 is 94483282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94483282 = 2 ⋅47241641.

It can be written as a sum of positive squares in 2 ways, for example, as 3168400 + 25070049 = 1780^2 + 5007^2 .

It is a cyclic number.

It is not a de Polignac number, because 28238449 - 2¹ = 28238447 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28238447) 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, 17592 + ... + 19129.

It is an arithmetic number, because the mean of its divisors is an integer number (7068985).

Almost surely, 2^28238449 is an apocalyptic number.

It is an amenable number.

28238449 is a deficient number, since it is larger than the sum of its proper divisors (37491).

28238449 is an equidigital number, since it uses as much as digits as its factorization.

28238449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37490.

The product of its digits is 110592, while the sum is 40.

The square root of 28238449 is about 5313.9861685932. The cubic root of 28238449 is about 304.5184517908.

The spelling of 28238449 in words is "twenty-eight million, two hundred thirty-eight thousand, four hundred forty-nine".