221220112213 has 4 divisors (see below), whose sum is σ = 226615724748. Its totient is φ = 215824499680.

The previous prime is 221220112207. The next prime is 221220112229. The reversal of 221220112213 is 312211022122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 312211022122 = 2 ⋅156105511061.

It can be written as a sum of positive squares in 2 ways, for example, as 130839911524 + 90380200689 = 361718^2 + 300633^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221220112213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221220112313) 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, 2697806206 + ... + 2697806287.

It is an arithmetic number, because the mean of its divisors is an integer number (56653931187).

Almost surely, 2^221220112213 is an apocalyptic number.

It is an amenable number.

221220112213 is a deficient number, since it is larger than the sum of its proper divisors (5395612535).

221220112213 is an equidigital number, since it uses as much as digits as its factorization.

221220112213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5395612534.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 221220112213 its reverse (312211022122), we get a palindrome (533431134335).

Subtracting 221220112213 from its reverse (312211022122), we obtain a palindrome (90990909909).

The spelling of 221220112213 in words is "two hundred twenty-one billion, two hundred twenty million, one hundred twelve thousand, two hundred thirteen".