211302311221 has 4 divisors (see below), whose sum is σ = 211421222572. Its totient is φ = 211183399872.

The previous prime is 211302311201. The next prime is 211302311251. The reversal of 211302311221 is 122113203112.

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 140553759025 + 70748552196 = 374905^2 + 265986^2 .

It is a cyclic number.

It is not a de Polignac number, because 211302311221 - 2²⁵ = 211268756789 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 (211302311201) 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, 59453010 + ... + 59456563.

It is an arithmetic number, because the mean of its divisors is an integer number (52855305643).

Almost surely, 2^211302311221 is an apocalyptic number.

It is an amenable number.

211302311221 is a deficient number, since it is larger than the sum of its proper divisors (118911351).

211302311221 is a wasteful number, since it uses less digits than its factorization.

211302311221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118911350.

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

Adding to 211302311221 its reverse (122113203112), we get a palindrome (333415514333).

The spelling of 211302311221 in words is "two hundred eleven billion, three hundred two million, three hundred eleven thousand, two hundred twenty-one".