8866072421821 has 2 divisors, whose sum is σ = 8866072421822. Its totient is φ = 8866072421820.

The previous prime is 8866072421809. The next prime is 8866072421839. The reversal of 8866072421821 is 1281242706688.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8349291156196 + 516781265625 = 2889514^2 + 718875^2 .

It is a cyclic number.

It is not a de Polignac number, because 8866072421821 - 2¹⁹ = 8866071897533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8866072421621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4433036210910 + 4433036210911.

It is an arithmetic number, because the mean of its divisors is an integer number (4433036210911).

Almost surely, 2^{8866072421821} is an apocalyptic number.

It is an amenable number.

8866072421821 is a deficient number, since it is larger than the sum of its proper divisors (1).

8866072421821 is an equidigital number, since it uses as much as digits as its factorization.

8866072421821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4128768, while the sum is 55.

The spelling of 8866072421821 in words is "eight trillion, eight hundred sixty-six billion, seventy-two million, four hundred twenty-one thousand, eight hundred twenty-one".