28728319 has 2 divisors, whose sum is σ = 28728320. Its totient is φ = 28728318.

The previous prime is 28728307. The next prime is 28728341. The reversal of 28728319 is 91382782.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28728319 - 2⁷ = 28728191 is a prime.

It is a super-2 number, since 2×28728319² = 1650632625131522, which contains 22 as substring.

It is a Chen prime.

It is equal to p_1783894 and since 28728319 and 1783894 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28728379) 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 as a sum of consecutive naturals, namely, 14364159 + 14364160.

It is an arithmetic number, because the mean of its divisors is an integer number (14364160).

Almost surely, 2^28728319 is an apocalyptic number.

28728319 is a deficient number, since it is larger than the sum of its proper divisors (1).

28728319 is an equidigital number, since it uses as much as digits as its factorization.

28728319 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 40.

The square root of 28728319 is about 5359.8805023993. The cubic root of 28728319 is about 306.2692569315.

The spelling of 28728319 in words is "twenty-eight million, seven hundred twenty-eight thousand, three hundred nineteen".