2001221021212 has 24 divisors (see below), whose sum is σ = 4002992009856. Its totient is φ = 857548301808.

The previous prime is 2001221021179. The next prime is 2001221021213. The reversal of 2001221021212 is 2121201221002.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001221021213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4702858 + ... + 5110705.

It is an arithmetic number, because the mean of its divisors is an integer number (166791333744).

Almost surely, 2^{2001221021212} is an apocalyptic number.

It is an amenable number.

2001221021212 is an abundant number, since it is smaller than the sum of its proper divisors (2001770988644).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2001221021212 is a wasteful number, since it uses less digits than its factorization.

2001221021212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9820857 (or 9820855 counting only the distinct ones).

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

Adding to 2001221021212 its reverse (2121201221002), we get a palindrome (4122422242214).

The spelling of 2001221021212 in words is "two trillion, one billion, two hundred twenty-one million, twenty-one thousand, two hundred twelve".