20002220021 has 4 divisors (see below), whose sum is σ = 22859680032. Its totient is φ = 17144760012.

The previous prime is 20002219969. The next prime is 20002220057. The reversal of 20002220021 is 12002220002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20002220021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20002219984 and 20002220011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20002220081) 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, 1428729995 + ... + 1428730008.

It is an arithmetic number, because the mean of its divisors is an integer number (5714920008).

Almost surely, 2^20002220021 is an apocalyptic number.

It is an amenable number.

20002220021 is a deficient number, since it is larger than the sum of its proper divisors (2857460011).

20002220021 is an equidigital number, since it uses as much as digits as its factorization.

20002220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2857460010.

The product of its (nonzero) digits is 32, while the sum is 11.

Adding to 20002220021 its reverse (12002220002), we get a palindrome (32004440023).

The spelling of 20002220021 in words is "twenty billion, two million, two hundred twenty thousand, twenty-one".