28577491 has 2 divisors, whose sum is σ = 28577492. Its totient is φ = 28577490.

The previous prime is 28577489. The next prime is 28577509. The reversal of 28577491 is 19477582.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28577491 - 2¹ = 28577489 is a prime.

Together with 28577489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28577191) 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, 14288745 + 14288746.

It is an arithmetic number, because the mean of its divisors is an integer number (14288746).

Almost surely, 2^28577491 is an apocalyptic number.

28577491 is a deficient number, since it is larger than the sum of its proper divisors (1).

28577491 is an equidigital number, since it uses as much as digits as its factorization.

28577491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 141120, while the sum is 43.

The square root of 28577491 is about 5345.7918964359. The cubic root of 28577491 is about 305.7323296127.

Subtracting from 28577491 its reverse (19477582), we obtain a palindrome (9099909).

The spelling of 28577491 in words is "twenty-eight million, five hundred seventy-seven thousand, four hundred ninety-one".