28790321 has 4 divisors (see below), whose sum is σ = 32903232. Its totient is φ = 24677412.

The previous prime is 28790303. The next prime is 28790371. The reversal of 28790321 is 12309782.

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.

It is a cyclic number.

It is not a de Polignac number, because 28790321 - 2¹⁴ = 28773937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28790371) 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, 2056445 + ... + 2056458.

It is an arithmetic number, because the mean of its divisors is an integer number (8225808).

Almost surely, 2^28790321 is an apocalyptic number.

It is an amenable number.

28790321 is a deficient number, since it is larger than the sum of its proper divisors (4112911).

28790321 is an equidigital number, since it uses as much as digits as its factorization.

28790321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4112910.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 28790321 is about 5365.6612826380. The cubic root of 28790321 is about 306.4894306423.

The spelling of 28790321 in words is "twenty-eight million, seven hundred ninety thousand, three hundred twenty-one".