28024013 has 4 divisors (see below), whose sum is σ = 28079580. Its totient is φ = 27968448.

The previous prime is 28023991. The next prime is 28024019. The reversal of 28024013 is 31042082.

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 13446889 + 14577124 = 3667^2 + 3818^2 .

It is a cyclic number.

It is not a de Polignac number, because 28024013 - 2⁸ = 28023757 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 (28024019) 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, 27020 + ... + 28037.

It is an arithmetic number, because the mean of its divisors is an integer number (7019895).

Almost surely, 2^28024013 is an apocalyptic number.

It is an amenable number.

28024013 is a deficient number, since it is larger than the sum of its proper divisors (55567).

28024013 is an equidigital number, since it uses as much as digits as its factorization.

28024013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55566.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 28024013 is about 5293.7711510794. The cubic root of 28024013 is about 303.7456790638.

Adding to 28024013 its reverse (31042082), we get a palindrome (59066095).

The spelling of 28024013 in words is "twenty-eight million, twenty-four thousand, thirteen".