28328257 has 2 divisors, whose sum is σ = 28328258. Its totient is φ = 28328256.

The previous prime is 28328243. The next prime is 28328281. The reversal of 28328257 is 75282382.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25492401 + 2835856 = 5049^2 + 1684^2 .

It is a cyclic number.

It is not a de Polignac number, because 28328257 - 2¹¹ = 28326209 is a prime.

It is not a weakly prime, because it can be changed into another prime (28328207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14164128 + 14164129.

It is an arithmetic number, because the mean of its divisors is an integer number (14164129).

Almost surely, 2^28328257 is an apocalyptic number.

It is an amenable number.

28328257 is a deficient number, since it is larger than the sum of its proper divisors (1).

28328257 is an equidigital number, since it uses as much as digits as its factorization.

28328257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 37.

The square root of 28328257 is about 5322.4296143773. The cubic root of 28328257 is about 304.8409347054.

The spelling of 28328257 in words is "twenty-eight million, three hundred twenty-eight thousand, two hundred fifty-seven".