221102120220221 has 4 divisors (see below), whose sum is σ = 221900322820572. Its totient is φ = 220303917619872.

The previous prime is 221102120219983. The next prime is 221102120220251. The reversal of 221102120220221 is 122022021201122.

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 95491710384196 + 125610409836025 = 9771986^2 + 11207605^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221102120220221 is a prime.

It is a super-2 number, since 2×221102120220221² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221102120220193 and 221102120220202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221102120220251) 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, 399101299760 + ... + 399101300313.

It is an arithmetic number, because the mean of its divisors is an integer number (55475080705143).

Almost surely, 2^{221102120220221} is an apocalyptic number.

It is an amenable number.

221102120220221 is a deficient number, since it is larger than the sum of its proper divisors (798202600351).

221102120220221 is an equidigital number, since it uses as much as digits as its factorization.

221102120220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 798202600350.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 221102120220221 its reverse (122022021201122), we get a palindrome (343124141421343).

The spelling of 221102120220221 in words is "two hundred twenty-one trillion, one hundred two billion, one hundred twenty million, two hundred twenty thousand, two hundred twenty-one".