28916557 has 2 divisors, whose sum is σ = 28916558. Its totient is φ = 28916556.

The previous prime is 28916539. The next prime is 28916561. The reversal of 28916557 is 75561982.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21846276 + 7070281 = 4674^2 + 2659^2 .

It is a cyclic number.

It is not a de Polignac number, because 28916557 - 2¹⁹ = 28392269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28916527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14458278 + 14458279.

It is an arithmetic number, because the mean of its divisors is an integer number (14458279).

Almost surely, 2^28916557 is an apocalyptic number.

It is an amenable number.

28916557 is a deficient number, since it is larger than the sum of its proper divisors (1).

28916557 is an equidigital number, since it uses as much as digits as its factorization.

28916557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 151200, while the sum is 43.

The square root of 28916557 is about 5377.4117380018. The cubic root of 28916557 is about 306.9367289955.

The spelling of 28916557 in words is "twenty-eight million, nine hundred sixteen thousand, five hundred fifty-seven".