28649813 has 2 divisors, whose sum is σ = 28649814. Its totient is φ = 28649812.

The previous prime is 28649783. The next prime is 28649827. The reversal of 28649813 is 31894682.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19298449 + 9351364 = 4393^2 + 3058^2 .

It is a cyclic number.

It is not a de Polignac number, because 28649813 - 2⁶ = 28649749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28649713) 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, 14324906 + 14324907.

It is an arithmetic number, because the mean of its divisors is an integer number (14324907).

Almost surely, 2^28649813 is an apocalyptic number.

It is an amenable number.

28649813 is a deficient number, since it is larger than the sum of its proper divisors (1).

28649813 is an equidigital number, since it uses as much as digits as its factorization.

28649813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 82944, while the sum is 41.

The square root of 28649813 is about 5352.5520081546. The cubic root of 28649813 is about 305.9900213187.

The spelling of 28649813 in words is "twenty-eight million, six hundred forty-nine thousand, eight hundred thirteen".