28557427 has 2 divisors, whose sum is σ = 28557428. Its totient is φ = 28557426.

The previous prime is 28557391. The next prime is 28557439. The reversal of 28557427 is 72475582.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28557427 - 2⁷ = 28557299 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28557427.

It is not a weakly prime, because it can be changed into another prime (28557457) 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 as a sum of consecutive naturals, namely, 14278713 + 14278714.

It is an arithmetic number, because the mean of its divisors is an integer number (14278714).

Almost surely, 2^28557427 is an apocalyptic number.

28557427 is a deficient number, since it is larger than the sum of its proper divisors (1).

28557427 is an equidigital number, since it uses as much as digits as its factorization.

28557427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 156800, while the sum is 40.

The square root of 28557427 is about 5343.9149506705. The cubic root of 28557427 is about 305.6607622194.

The spelling of 28557427 in words is "twenty-eight million, five hundred fifty-seven thousand, four hundred twenty-seven".