201221102021 has 48 divisors (see below), whose sum is σ = 227391805440. Its totient is φ = 177746472960.

The previous prime is 201221102009. The next prime is 201221102053. The reversal of 201221102021 is 120201122102.

It is not a de Polignac number, because 201221102021 - 2¹⁸ = 201220839877 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 201221101987 and 201221102005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201221102081) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 47579135 + ... + 47583363.

It is an arithmetic number, because the mean of its divisors is an integer number (4737329280).

Almost surely, 2^201221102021 is an apocalyptic number.

It is an amenable number.

201221102021 is a deficient number, since it is larger than the sum of its proper divisors (26170703419).

201221102021 is a wasteful number, since it uses less digits than its factorization.

201221102021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4454 (or 4437 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 201221102021 its reverse (120201122102), we get a palindrome (321422224123).

The spelling of 201221102021 in words is "two hundred one billion, two hundred twenty-one million, one hundred two thousand, twenty-one".