8809440821 has 2 divisors, whose sum is σ = 8809440822. Its totient is φ = 8809440820.

The previous prime is 8809440799. The next prime is 8809440883. The reversal of 8809440821 is 1280449088.

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., 7618845796 + 1190595025 = 87286^2 + 34505^2 .

It is a cyclic number.

It is not a de Polignac number, because 8809440821 - 2²² = 8805246517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8809442821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4404720410 + 4404720411.

It is an arithmetic number, because the mean of its divisors is an integer number (4404720411).

Almost surely, 2^8809440821 is an apocalyptic number.

It is an amenable number.

8809440821 is a deficient number, since it is larger than the sum of its proper divisors (1).

8809440821 is an equidigital number, since it uses as much as digits as its factorization.

8809440821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 147456, while the sum is 44.

The square root of 8809440821 is about 93858.6214526934. The cubic root of 8809440821 is about 2065.2982679418.

The spelling of 8809440821 in words is "eight billion, eight hundred nine million, four hundred forty thousand, eight hundred twenty-one".