211023311221 has 4 divisors (see below), whose sum is σ = 211024641100. Its totient is φ = 211021981344.

The previous prime is 211023311209. The next prime is 211023311251. The reversal of 211023311221 is 122113320112.

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 44865170596 + 166158140625 = 211814^2 + 407625^2 .

It is a cyclic number.

It is not a de Polignac number, because 211023311221 - 2¹¹ = 211023309173 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 (211023311251) 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, 388656 + ... + 757033.

It is an arithmetic number, because the mean of its divisors is an integer number (52756160275).

Almost surely, 2^211023311221 is an apocalyptic number.

It is an amenable number.

211023311221 is a deficient number, since it is larger than the sum of its proper divisors (1329879).

211023311221 is a wasteful number, since it uses less digits than its factorization.

211023311221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1329878.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 211023311221 its reverse (122113320112), we get a palindrome (333136631333).

The spelling of 211023311221 in words is "two hundred eleven billion, twenty-three million, three hundred eleven thousand, two hundred twenty-one".