20000321021 has 4 divisors (see below), whose sum is σ = 20012108412. Its totient is φ = 19988533632.

The previous prime is 20000320943. The next prime is 20000321053. The reversal of 20000321021 is 12012300002.

It is a happy number.

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 8144160025 + 11856160996 = 90245^2 + 108886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20000321021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20000320993 and 20000321011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20000321821) 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 3 ways as a sum of consecutive naturals, for example, 5891150 + ... + 5894543.

It is an arithmetic number, because the mean of its divisors is an integer number (5003027103).

Almost surely, 2^20000321021 is an apocalyptic number.

It is an amenable number.

20000321021 is a deficient number, since it is larger than the sum of its proper divisors (11787391).

20000321021 is a wasteful number, since it uses less digits than its factorization.

20000321021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11787390.

The product of its (nonzero) digits is 24, while the sum is 11.

Adding to 20000321021 its reverse (12012300002), we get a palindrome (32012621023).

The spelling of 20000321021 in words is "twenty billion, three hundred twenty-one thousand, twenty-one".