845804574721 has 2 divisors, whose sum is σ = 845804574722. Its totient is φ = 845804574720.

The previous prime is 845804574697. The next prime is 845804574749. The reversal of 845804574721 is 127475408548.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 689672116225 + 156132458496 = 830465^2 + 395136^2 .

It is a cyclic number.

It is not a de Polignac number, because 845804574721 - 2³⁵ = 811444836353 is a prime.

It is not a weakly prime, because it can be changed into another prime (845804574751) 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, 422902287360 + 422902287361.

It is an arithmetic number, because the mean of its divisors is an integer number (422902287361).

Almost surely, 2^845804574721 is an apocalyptic number.

It is an amenable number.

845804574721 is a deficient number, since it is larger than the sum of its proper divisors (1).

845804574721 is an equidigital number, since it uses as much as digits as its factorization.

845804574721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10035200, while the sum is 55.

The spelling of 845804574721 in words is "eight hundred forty-five billion, eight hundred four million, five hundred seventy-four thousand, seven hundred twenty-one".