28540760221 has 2 divisors, whose sum is σ = 28540760222. Its totient is φ = 28540760220.

The previous prime is 28540760179. The next prime is 28540760243. The reversal of 28540760221 is 12206704582.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17804899225 + 10735860996 = 133435^2 + 103614^2 .

It is a cyclic number.

It is not a de Polignac number, because 28540760221 - 2¹⁷ = 28540629149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28540760251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14270380110 + 14270380111.

It is an arithmetic number, because the mean of its divisors is an integer number (14270380111).

Almost surely, 2^28540760221 is an apocalyptic number.

It is an amenable number.

28540760221 is a deficient number, since it is larger than the sum of its proper divisors (1).

28540760221 is an equidigital number, since it uses as much as digits as its factorization.

28540760221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 53760, while the sum is 37.

The spelling of 28540760221 in words is "twenty-eight billion, five hundred forty million, seven hundred sixty thousand, two hundred twenty-one".