202021221202021 has 16 divisors (see below), whose sum is σ = 219722899178160. Its totient is φ = 184631893770240.

The previous prime is 202021221201977. The next prime is 202021221202081. The reversal of 202021221202021 is 120202122120202.

It can be written as a sum of positive squares in 8 ways, for example, as 126890897751396 + 75130323450625 = 11264586^2 + 8667775^2 .

It is a cyclic number.

It is not a de Polignac number, because 202021221202021 - 2¹³ = 202021221193829 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 202021221202021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202021221202081) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72651960 + ... + 75381361.

It is an arithmetic number, because the mean of its divisors is an integer number (13732681198635).

Almost surely, 2^{202021221202021} is an apocalyptic number.

It is an amenable number.

202021221202021 is a deficient number, since it is larger than the sum of its proper divisors (17701677976139).

202021221202021 is a wasteful number, since it uses less digits than its factorization.

202021221202021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148034376.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 202021221202021 its reverse (120202122120202), we get a palindrome (322223343322223).

The spelling of 202021221202021 in words is "two hundred two trillion, twenty-one billion, two hundred twenty-one million, two hundred two thousand, twenty-one".