2122121200021 has 4 divisors (see below), whose sum is σ = 2122154131552. Its totient is φ = 2122088268492.

The previous prime is 2122121199953. The next prime is 2122121200033. The reversal of 2122121200021 is 1200021212212.

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 a cyclic number.

It is not a de Polignac number, because 2122121200021 - 2⁷ = 2122121199893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2122121199968 and 2122121200004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2122121200051) 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, 16368915 + ... + 16498048.

It is an arithmetic number, because the mean of its divisors is an integer number (530538532888).

Almost surely, 2^{2122121200021} is an apocalyptic number.

It is an amenable number.

2122121200021 is a deficient number, since it is larger than the sum of its proper divisors (32931531).

2122121200021 is an equidigital number, since it uses as much as digits as its factorization.

2122121200021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32931530.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 2122121200021 its reverse (1200021212212), we get a palindrome (3322142412233).

It can be divided in two parts, 212212 and 1200021, that multiplied together give a palindrome (254658856452).

The spelling of 2122121200021 in words is "two trillion, one hundred twenty-two billion, one hundred twenty-one million, two hundred thousand, twenty-one".