20121222200021 has 4 divisors (see below), whose sum is σ = 20996057947872. Its totient is φ = 19246386452172.

The previous prime is 20121222199987. The next prime is 20121222200141. The reversal of 20121222200021 is 12000222212102.

It is a happy number.

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 not a de Polignac number, because 20121222200021 - 2¹⁰ = 20121222198997 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 (20121222206021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 437417873891 + ... + 437417873936.

It is an arithmetic number, because the mean of its divisors is an integer number (5249014486968).

Almost surely, 2^{20121222200021} is an apocalyptic number.

It is an amenable number.

20121222200021 is a deficient number, since it is larger than the sum of its proper divisors (874835747851).

20121222200021 is an equidigital number, since it uses as much as digits as its factorization.

20121222200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 874835747850.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 20121222200021 its reverse (12000222212102), we get a palindrome (32121444412123).

The spelling of 20121222200021 in words is "twenty trillion, one hundred twenty-one billion, two hundred twenty-two million, two hundred thousand, twenty-one".