20052821 has 2 divisors, whose sum is σ = 20052822. Its totient is φ = 20052820.

The previous prime is 20052811. The next prime is 20052869. The reversal of 20052821 is 12825002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19704721 + 348100 = 4439^2 + 590^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20052821 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20052793 and 20052802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20052811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10026410 + 10026411.

It is an arithmetic number, because the mean of its divisors is an integer number (10026411).

Almost surely, 2^20052821 is an apocalyptic number.

It is an amenable number.

20052821 is a deficient number, since it is larger than the sum of its proper divisors (1).

20052821 is an equidigital number, since it uses as much as digits as its factorization.

20052821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 20052821 is about 4478.0376282474. The cubic root of 20052821 is about 271.6805153508.

Adding to 20052821 its reverse (12825002), we get a palindrome (32877823).

The spelling of 20052821 in words is "twenty million, fifty-two thousand, eight hundred twenty-one".