2002122121221 has 6 divisors (see below), whose sum is σ = 2891954175110. Its totient is φ = 1334748080808.

The previous prime is 2002122121189. The next prime is 2002122121247. The reversal of 2002122121221 is 1221212212002.

It is a happy number.

2002122121221 is a `hidden beast` number, since 20 + 0 + 212 + 212 + 1 + 221 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1761420024225 + 240702096996 = 1327185^2 + 490614^2 .

It is not a de Polignac number, because 2002122121221 - 2⁵ = 2002122121189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2002122121194 and 2002122121203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2002122121421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 111229006726 + ... + 111229006743.

Almost surely, 2^{2002122121221} is an apocalyptic number.

It is an amenable number.

2002122121221 is a deficient number, since it is larger than the sum of its proper divisors (889832053889).

2002122121221 is a wasteful number, since it uses less digits than its factorization.

2002122121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222458013475 (or 222458013472 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 2002122121221 its reverse (1221212212002), we get a palindrome (3223334333223).

It can be divided in two parts, 2002 and 122121221, that multiplied together give a palindrome (244486684442).

The spelling of 2002122121221 in words is "two trillion, two billion, one hundred twenty-two million, one hundred twenty-one thousand, two hundred twenty-one".