28753321 has 4 divisors (see below), whose sum is σ = 28972944. Its totient is φ = 28533700.

The previous prime is 28753279. The next prime is 28753339. The reversal of 28753321 is 12335782.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12335782 = 2 ⋅6167891.

It is a cyclic number.

It is not a de Polignac number, because 28753321 - 2¹⁵ = 28720553 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28753121) 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, 109615 + ... + 109876.

It is an arithmetic number, because the mean of its divisors is an integer number (7243236).

Almost surely, 2^28753321 is an apocalyptic number.

It is an amenable number.

28753321 is a deficient number, since it is larger than the sum of its proper divisors (219623).

28753321 is a wasteful number, since it uses less digits than its factorization.

28753321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219622.

The product of its digits is 10080, while the sum is 31.

The square root of 28753321 is about 5362.2123232860. The cubic root of 28753321 is about 306.3580789711.

The spelling of 28753321 in words is "twenty-eight million, seven hundred fifty-three thousand, three hundred twenty-one".