20421222005 has 4 divisors (see below), whose sum is σ = 24505466412. Its totient is φ = 16336977600.

The previous prime is 20421221987. The next prime is 20421222043. The reversal of 20421222005 is 50022212402.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2775287761 + 17645934244 = 52681^2 + 132838^2 .

It is not a de Polignac number, because 20421222005 - 2⁶ = 20421221941 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 2042122196 + ... + 2042122205.

It is an arithmetic number, because the mean of its divisors is an integer number (6126366603).

Almost surely, 2^20421222005 is an apocalyptic number.

It is an amenable number.

20421222005 is a deficient number, since it is larger than the sum of its proper divisors (4084244407).

20421222005 is an equidigital number, since it uses as much as digits as its factorization.

20421222005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4084244406.

The product of its (nonzero) digits is 640, while the sum is 20.

Adding to 20421222005 its reverse (50022212402), we get a palindrome (70443434407).

The spelling of 20421222005 in words is "twenty billion, four hundred twenty-one million, two hundred twenty-two thousand, five".