28032857 has 2 divisors, whose sum is σ = 28032858. Its totient is φ = 28032856.

The previous prime is 28032839. The next prime is 28032863. The reversal of 28032857 is 75823082.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17606416 + 10426441 = 4196^2 + 3229^2 .

It is a cyclic number.

It is not a de Polignac number, because 28032857 - 2⁶ = 28032793 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28032817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14016428 + 14016429.

It is an arithmetic number, because the mean of its divisors is an integer number (14016429).

Almost surely, 2^28032857 is an apocalyptic number.

It is an amenable number.

28032857 is a deficient number, since it is larger than the sum of its proper divisors (1).

28032857 is an equidigital number, since it uses as much as digits as its factorization.

28032857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26880, while the sum is 35.

The square root of 28032857 is about 5294.6064065235. The cubic root of 28032857 is about 303.7776283810. Note that the first 3 decimals are identical.

The spelling of 28032857 in words is "twenty-eight million, thirty-two thousand, eight hundred fifty-seven".