28771489 has 2 divisors, whose sum is σ = 28771490. Its totient is φ = 28771488.

The previous prime is 28771481. The next prime is 28771493. The reversal of 28771489 is 98417782.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26697889 + 2073600 = 5167^2 + 1440^2 .

It is a cyclic number.

It is not a de Polignac number, because 28771489 - 2³ = 28771481 is a prime.

It is not a weakly prime, because it can be changed into another prime (28771481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14385744 + 14385745.

It is an arithmetic number, because the mean of its divisors is an integer number (14385745).

Almost surely, 2^28771489 is an apocalyptic number.

It is an amenable number.

28771489 is a deficient number, since it is larger than the sum of its proper divisors (1).

28771489 is an equidigital number, since it uses as much as digits as its factorization.

28771489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 225792, while the sum is 46.

The square root of 28771489 is about 5363.9061326612. The cubic root of 28771489 is about 306.4225902636.

The spelling of 28771489 in words is "twenty-eight million, seven hundred seventy-one thousand, four hundred eighty-nine".