221011121010221 has 4 divisors (see below), whose sum is σ = 221041660069692. Its totient is φ = 220980581950752.

The previous prime is 221011121010181. The next prime is 221011121010247. The reversal of 221011121010221 is 122010121110122.

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 184328547865225 + 36682573144996 = 13576765^2 + 6056614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221011121010221 is a prime.

It is a super-2 number, since 2×221011121010221² (a number of 29 digits) contains 22 as substring.

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 221011121010221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221011121016221) 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 3 ways as a sum of consecutive naturals, for example, 15269518880 + ... + 15269533353.

It is an arithmetic number, because the mean of its divisors is an integer number (55260415017423).

Almost surely, 2^{221011121010221} is an apocalyptic number.

It is an amenable number.

221011121010221 is a deficient number, since it is larger than the sum of its proper divisors (30539059471).

221011121010221 is an equidigital number, since it uses as much as digits as its factorization.

221011121010221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30539059470.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 221011121010221 its reverse (122010121110122), we get a palindrome (343021242120343).

Subtracting from 221011121010221 its reverse (122010121110122), we obtain a palindrome (99000999900099).

The spelling of 221011121010221 in words is "two hundred twenty-one trillion, eleven billion, one hundred twenty-one million, ten thousand, two hundred twenty-one".