28778837 has 2 divisors, whose sum is σ = 28778838. Its totient is φ = 28778836.

The previous prime is 28778821. The next prime is 28778857. The reversal of 28778837 is 73887782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27447121 + 1331716 = 5239^2 + 1154^2 .

It is a cyclic number.

It is not a de Polignac number, because 28778837 - 2⁴ = 28778821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28778857) 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, 14389418 + 14389419.

It is an arithmetic number, because the mean of its divisors is an integer number (14389419).

Almost surely, 2^28778837 is an apocalyptic number.

It is an amenable number.

28778837 is a deficient number, since it is larger than the sum of its proper divisors (1).

28778837 is an equidigital number, since it uses as much as digits as its factorization.

28778837 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1053696, while the sum is 50.

The square root of 28778837 is about 5364.5910375349. The cubic root of 28778837 is about 306.4486739738.

The spelling of 28778837 in words is "twenty-eight million, seven hundred seventy-eight thousand, eight hundred thirty-seven".