28303764721 has 2 divisors, whose sum is σ = 28303764722. Its totient is φ = 28303764720.

The previous prime is 28303764719. The next prime is 28303764791. The reversal of 28303764721 is 12746730382.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28269378225 + 34386496 = 168135^2 + 5864^2 .

It is a cyclic number.

It is not a de Polignac number, because 28303764721 - 2¹ = 28303764719 is a prime.

It is a super-2 number, since 2×28303764721² (a number of 22 digits) contains 22 as substring.

Together with 28303764719, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28303764791) 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, 14151882360 + 14151882361.

It is an arithmetic number, because the mean of its divisors is an integer number (14151882361).

Almost surely, 2^28303764721 is an apocalyptic number.

It is an amenable number.

28303764721 is a deficient number, since it is larger than the sum of its proper divisors (1).

28303764721 is an equidigital number, since it uses as much as digits as its factorization.

28303764721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 338688, while the sum is 43.

The spelling of 28303764721 in words is "twenty-eight billion, three hundred three million, seven hundred sixty-four thousand, seven hundred twenty-one".