20520044221 has 2 divisors, whose sum is σ = 20520044222. Its totient is φ = 20520044220.

The previous prime is 20520044201. The next prime is 20520044249. The reversal of 20520044221 is 12244002502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19913160996 + 606883225 = 141114^2 + 24635^2 .

It is a cyclic number.

It is not a de Polignac number, because 20520044221 - 2⁵ = 20520044189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20520044192 and 20520044201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20520044201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10260022110 + 10260022111.

It is an arithmetic number, because the mean of its divisors is an integer number (10260022111).

Almost surely, 2^20520044221 is an apocalyptic number.

It is an amenable number.

20520044221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20520044221 is an equidigital number, since it uses as much as digits as its factorization.

20520044221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1280, while the sum is 22.

Adding to 20520044221 its reverse (12244002502), we get a palindrome (32764046723).

The spelling of 20520044221 in words is "twenty billion, five hundred twenty million, forty-four thousand, two hundred twenty-one".