221202221011021 has 4 divisors (see below), whose sum is σ = 222480846566172. Its totient is φ = 219923595455872.

The previous prime is 221202221010839. The next prime is 221202221011087. The reversal of 221202221011021 is 120110122202122.

221202221011021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 209476123424100 + 11726097586921 = 14473290^2 + 3424339^2 .

It is a cyclic number.

It is not a de Polignac number, because 221202221011021 - 2³⁷ = 221064782057549 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 221202221011021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221202221012021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 639312777316 + ... + 639312777661.

It is an arithmetic number, because the mean of its divisors is an integer number (55620211641543).

Almost surely, 2^{221202221011021} is an apocalyptic number.

It is an amenable number.

221202221011021 is a deficient number, since it is larger than the sum of its proper divisors (1278625555151).

221202221011021 is a wasteful number, since it uses less digits than its factorization.

221202221011021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1278625555150.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 221202221011021 its reverse (120110122202122), we get a palindrome (341312343213143).

The spelling of 221202221011021 in words is "two hundred twenty-one trillion, two hundred two billion, two hundred twenty-one million, eleven thousand, twenty-one".