213122323031221 has 4 divisors (see below), whose sum is σ = 214354243973772. Its totient is φ = 211890402088672.

The previous prime is 213122323031201. The next prime is 213122323031231. The reversal of 213122323031221 is 122130323221312.

213122323031221 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 100169852063121 + 112952470968100 = 10008489^2 + 10627910^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213122323031221 is a prime.

It is a super-2 number, since 2×213122323031221² (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 213122323031221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213122323031201) 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, 615960471016 + ... + 615960471361.

It is an arithmetic number, because the mean of its divisors is an integer number (53588560993443).

Almost surely, 2^{213122323031221} is an apocalyptic number.

It is an amenable number.

213122323031221 is a deficient number, since it is larger than the sum of its proper divisors (1231920942551).

213122323031221 is a wasteful number, since it uses less digits than its factorization.

213122323031221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1231920942550.

The product of its (nonzero) digits is 5184, while the sum is 28.

Adding to 213122323031221 its reverse (122130323221312), we get a palindrome (335252646252533).

The spelling of 213122323031221 in words is "two hundred thirteen trillion, one hundred twenty-two billion, three hundred twenty-three million, thirty-one thousand, two hundred twenty-one".