20534343221 has 6 divisors (see below), whose sum is σ = 23886889110. Its totient is φ = 17600865576.

The previous prime is 20534343169. The next prime is 20534343227. The reversal of 20534343221 is 12234343502.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20521995025 + 12348196 = 143255^2 + 3514^2 .

It is not a de Polignac number, because 20534343221 - 2¹⁰ = 20534342197 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20534343227) 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 in 5 ways as a sum of consecutive naturals, for example, 209534066 + ... + 209534163.

It is an arithmetic number, because the mean of its divisors is an integer number (3981148185).

Almost surely, 2^20534343221 is an apocalyptic number.

It is an amenable number.

20534343221 is a deficient number, since it is larger than the sum of its proper divisors (3352545889).

20534343221 is an equidigital number, since it uses as much as digits as its factorization.

20534343221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419068243 (or 419068236 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 29.

Adding to 20534343221 its reverse (12234343502), we get a palindrome (32768686723).

The spelling of 20534343221 in words is "twenty billion, five hundred thirty-four million, three hundred forty-three thousand, two hundred twenty-one".