20112122210021 has 4 divisors (see below), whose sum is σ = 20116864520844. Its totient is φ = 20107379899200.

The previous prime is 20112122210003. The next prime is 20112122210027. The reversal of 20112122210021 is 12001222121102.

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 15994120540225 + 4118001669796 = 3999265^2 + 2029286^2 .

It is a cyclic number.

It is not a de Polignac number, because 20112122210021 - 2²⁶ = 20112055101157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20112122210027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2371149050 + ... + 2371157531.

It is an arithmetic number, because the mean of its divisors is an integer number (5029216130211).

Almost surely, 2^{20112122210021} is an apocalyptic number.

It is an amenable number.

20112122210021 is a deficient number, since it is larger than the sum of its proper divisors (4742310823).

20112122210021 is an equidigital number, since it uses as much as digits as its factorization.

20112122210021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4742310822.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 20112122210021 its reverse (12001222121102), we get a palindrome (32113344331123).

The spelling of 20112122210021 in words is "twenty trillion, one hundred twelve billion, one hundred twenty-two million, two hundred ten thousand, twenty-one".