20331324821 has 2 divisors, whose sum is σ = 20331324822. Its totient is φ = 20331324820.

The previous prime is 20331324799. The next prime is 20331324829. The reversal of 20331324821 is 12842313302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15592516900 + 4738807921 = 124870^2 + 68839^2 .

It is a cyclic number.

It is not a de Polignac number, because 20331324821 - 2¹⁰ = 20331323797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20331324829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10165662410 + 10165662411.

It is an arithmetic number, because the mean of its divisors is an integer number (10165662411).

Almost surely, 2^20331324821 is an apocalyptic number.

It is an amenable number.

20331324821 is a deficient number, since it is larger than the sum of its proper divisors (1).

20331324821 is an equidigital number, since it uses as much as digits as its factorization.

20331324821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 29.

The spelling of 20331324821 in words is "twenty billion, three hundred thirty-one million, three hundred twenty-four thousand, eight hundred twenty-one".