28511489 has 2 divisors, whose sum is σ = 28511490. Its totient is φ = 28511488.

The previous prime is 28511479. The next prime is 28511491. The reversal of 28511489 is 98411582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21003889 + 7507600 = 4583^2 + 2740^2 .

It is a cyclic number.

It is not a de Polignac number, because 28511489 - 2¹² = 28507393 is a prime.

Together with 28511491, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28511449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14255744 + 14255745.

It is an arithmetic number, because the mean of its divisors is an integer number (14255745).

Almost surely, 2^28511489 is an apocalyptic number.

It is an amenable number.

28511489 is a deficient number, since it is larger than the sum of its proper divisors (1).

28511489 is an equidigital number, since it uses as much as digits as its factorization.

28511489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23040, while the sum is 38.

The square root of 28511489 is about 5339.6150610320. The cubic root of 28511489 is about 305.4967770917.

The spelling of 28511489 in words is "twenty-eight million, five hundred eleven thousand, four hundred eighty-nine".