28321019 has 4 divisors (see below), whose sum is σ = 28785360. Its totient is φ = 27856680.

The previous prime is 28320979. The next prime is 28321061. The reversal of 28321019 is 91012382.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28321019 - 2¹² = 28316923 is a prime.

It is a super-2 number, since 2×28321019² = 1604160234396722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28321079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 232079 + ... + 232200.

It is an arithmetic number, because the mean of its divisors is an integer number (7196340).

Almost surely, 2^28321019 is an apocalyptic number.

28321019 is a deficient number, since it is larger than the sum of its proper divisors (464341).

28321019 is an equidigital number, since it uses as much as digits as its factorization.

28321019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464340.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 28321019 is about 5321.7496183116. The cubic root of 28321019 is about 304.8149697401.

The spelling of 28321019 in words is "twenty-eight million, three hundred twenty-one thousand, nineteen".