8445252721 has 2 divisors, whose sum is σ = 8445252722. Its totient is φ = 8445252720.

The previous prime is 8445252709. The next prime is 8445252727. The reversal of 8445252721 is 1272525448.

It is a happy number.

8445252721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7313670400 + 1131582321 = 85520^2 + 33639^2 .

It is a cyclic number.

It is not a de Polignac number, because 8445252721 - 2⁹ = 8445252209 is a prime.

It is not a weakly prime, because it can be changed into another prime (8445252727) 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, 4222626360 + 4222626361.

It is an arithmetic number, because the mean of its divisors is an integer number (4222626361).

Almost surely, 2^8445252721 is an apocalyptic number.

It is an amenable number.

8445252721 is a deficient number, since it is larger than the sum of its proper divisors (1).

8445252721 is an equidigital number, since it uses as much as digits as its factorization.

8445252721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 179200, while the sum is 40.

The square root of 8445252721 is about 91898.0561328693. The cubic root of 8445252721 is about 2036.4365511231.

The spelling of 8445252721 in words is "eight billion, four hundred forty-five million, two hundred fifty-two thousand, seven hundred twenty-one".