28313321 has 2 divisors, whose sum is σ = 28313322. Its totient is φ = 28313320.

The previous prime is 28313291. The next prime is 28313339. The reversal of 28313321 is 12331382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18826921 + 9486400 = 4339^2 + 3080^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28313321 is a prime.

It is not a weakly prime, because it can be changed into another prime (28313371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14156660 + 14156661.

It is an arithmetic number, because the mean of its divisors is an integer number (14156661).

Almost surely, 2^28313321 is an apocalyptic number.

It is an amenable number.

28313321 is a deficient number, since it is larger than the sum of its proper divisors (1).

28313321 is an equidigital number, since it uses as much as digits as its factorization.

28313321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 23.

The square root of 28313321 is about 5321.0263107788. The cubic root of 28313321 is about 304.7873497562.

The spelling of 28313321 in words is "twenty-eight million, three hundred thirteen thousand, three hundred twenty-one".