28378901 has 2 divisors, whose sum is σ = 28378902. Its totient is φ = 28378900.

The previous prime is 28378853. The next prime is 28378937. The reversal of 28378901 is 10987382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27615025 + 763876 = 5255^2 + 874^2 .

It is a cyclic number.

It is not a de Polignac number, because 28378901 - 2¹⁸ = 28116757 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28378991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14189450 + 14189451.

It is an arithmetic number, because the mean of its divisors is an integer number (14189451).

Almost surely, 2^28378901 is an apocalyptic number.

It is an amenable number.

28378901 is a deficient number, since it is larger than the sum of its proper divisors (1).

28378901 is an equidigital number, since it uses as much as digits as its factorization.

28378901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 28378901 is about 5327.1850915845. The cubic root of 28378901 is about 305.0224869204.

The spelling of 28378901 in words is "twenty-eight million, three hundred seventy-eight thousand, nine hundred one".