20043421205 has 4 divisors (see below), whose sum is σ = 24052105452. Its totient is φ = 16034736960.

The previous prime is 20043421199. The next prime is 20043421259. The reversal of 20043421205 is 50212434002.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50212434002 = 2 ⋅25106217001.

It can be written as a sum of positive squares in 2 ways, for example, as 7151408356 + 12892012849 = 84566^2 + 113543^2 .

It is not a de Polignac number, because 20043421205 - 2¹² = 20043417109 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, 2004342116 + ... + 2004342125.

It is an arithmetic number, because the mean of its divisors is an integer number (6013026363).

Almost surely, 2^20043421205 is an apocalyptic number.

It is an amenable number.

20043421205 is a deficient number, since it is larger than the sum of its proper divisors (4008684247).

20043421205 is an equidigital number, since it uses as much as digits as its factorization.

20043421205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4008684246.

The product of its (nonzero) digits is 1920, while the sum is 23.

Adding to 20043421205 its reverse (50212434002), we get a palindrome (70255855207).

The spelling of 20043421205 in words is "twenty billion, forty-three million, four hundred twenty-one thousand, two hundred five".