28965821 has 2 divisors, whose sum is σ = 28965822. Its totient is φ = 28965820.

The previous prime is 28965791. The next prime is 28965829. The reversal of 28965821 is 12856982.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25502500 + 3463321 = 5050^2 + 1861^2 .

It is a cyclic number.

It is not a de Polignac number, because 28965821 - 2²² = 24771517 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28965829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14482910 + 14482911.

It is an arithmetic number, because the mean of its divisors is an integer number (14482911).

Almost surely, 2^28965821 is an apocalyptic number.

It is an amenable number.

28965821 is a deficient number, since it is larger than the sum of its proper divisors (1).

28965821 is an equidigital number, since it uses as much as digits as its factorization.

28965821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69120, while the sum is 41.

The square root of 28965821 is about 5381.9904310580. The cubic root of 28965821 is about 307.1109354447.

The spelling of 28965821 in words is "twenty-eight million, nine hundred sixty-five thousand, eight hundred twenty-one".