28553213 has 4 divisors (see below), whose sum is σ = 30749628. Its totient is φ = 26356800.

The previous prime is 28553209. The next prime is 28553249. The reversal of 28553213 is 31235582.

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 15578809 + 12974404 = 3947^2 + 3602^2 .

It is a cyclic number.

It is not a de Polignac number, because 28553213 - 2² = 28553209 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28553113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1098188 + ... + 1098213.

It is an arithmetic number, because the mean of its divisors is an integer number (7687407).

Almost surely, 2^28553213 is an apocalyptic number.

It is an amenable number.

28553213 is a deficient number, since it is larger than the sum of its proper divisors (2196415).

28553213 is a wasteful number, since it uses less digits than its factorization.

28553213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2196414.

The product of its digits is 7200, while the sum is 29.

The square root of 28553213 is about 5343.5206558972. The cubic root of 28553213 is about 305.6457268100.

Adding to 28553213 its reverse (31235582), we get a palindrome (59788795).

The spelling of 28553213 in words is "twenty-eight million, five hundred fifty-three thousand, two hundred thirteen".