20045223521 has 2 divisors, whose sum is σ = 20045223522. Its totient is φ = 20045223520.

The previous prime is 20045223493. The next prime is 20045223529. The reversal of 20045223521 is 12532254002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17150783521 + 2894440000 = 130961^2 + 53800^2 .

It is a cyclic number.

It is not a de Polignac number, because 20045223521 - 2¹⁴ = 20045207137 is a prime.

It is not a weakly prime, because it can be changed into another prime (20045223529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10022611760 + 10022611761.

It is an arithmetic number, because the mean of its divisors is an integer number (10022611761).

Almost surely, 2^20045223521 is an apocalyptic number.

It is an amenable number.

20045223521 is a deficient number, since it is larger than the sum of its proper divisors (1).

20045223521 is an equidigital number, since it uses as much as digits as its factorization.

20045223521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 26.

Adding to 20045223521 its reverse (12532254002), we get a palindrome (32577477523).

The spelling of 20045223521 in words is "twenty billion, forty-five million, two hundred twenty-three thousand, five hundred twenty-one".