2001202021221 has 16 divisors (see below), whose sum is σ = 2972607778560. Its totient is φ = 1189043110080.

The previous prime is 2001202021219. The next prime is 2001202021243. The reversal of 2001202021221 is 1221202021002.

It is not a de Polignac number, because 2001202021221 - 2¹ = 2001202021219 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2001202021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001202021271) 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 15 ways as a sum of consecutive naturals, for example, 884703565 + ... + 884705826.

It is an arithmetic number, because the mean of its divisors is an integer number (185787986160).

Almost surely, 2^{2001202021221} is an apocalyptic number.

It is an amenable number.

2001202021221 is a deficient number, since it is larger than the sum of its proper divisors (971405757339).

2001202021221 is a wasteful number, since it uses less digits than its factorization.

2001202021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1769409436.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 2001202021221 its reverse (1221202021002), we get a palindrome (3222404042223).

The spelling of 2001202021221 in words is "two trillion, one billion, two hundred two million, twenty-one thousand, two hundred twenty-one".