2002121212221 has 24 divisors (see below), whose sum is σ = 3297611411640. Its totient is φ = 1159599614976.

The previous prime is 2002121212219. The next prime is 2002121212241. The reversal of 2002121212221 is 1222121212002.

It is a happy number.

2002121212221 is a `hidden beast` number, since 20 + 0 + 212 + 1 + 212 + 221 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 63103952025 + 1939017260196 = 251205^2 + 1392486^2 .

It is not a de Polignac number, because 2002121212221 - 2¹ = 2002121212219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2002121212194 and 2002121212203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2002121212241) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 503296456 + ... + 503300433.

It is an arithmetic number, because the mean of its divisors is an integer number (137400475485).

Almost surely, 2^{2002121212221} is an apocalyptic number.

It is an amenable number.

2002121212221 is a deficient number, since it is larger than the sum of its proper divisors (1295490199419).

2002121212221 is a wasteful number, since it uses less digits than its factorization.

2002121212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1006596925 (or 1006596922 counting only the distinct ones).

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

Adding to 2002121212221 its reverse (1222121212002), we get a palindrome (3224242424223).

The spelling of 2002121212221 in words is "two trillion, two billion, one hundred twenty-one million, two hundred twelve thousand, two hundred twenty-one".