211133221 has 12 divisors (see below), whose sum is σ = 229097700. Its totient is φ = 194488320.

The previous prime is 211133213. The next prime is 211133249. The reversal of 211133221 is 122331112.

It can be written as a sum of positive squares in 6 ways, for example, as 12321 + 211120900 = 111^2 + 14530^2 .

It is not a de Polignac number, because 211133221 - 2³ = 211133213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211133195 and 211133204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211133521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 107355 + ... + 109303.

It is an arithmetic number, because the mean of its divisors is an integer number (19091475).

Almost surely, 2^211133221 is an apocalyptic number.

It is an amenable number.

211133221 is a deficient number, since it is larger than the sum of its proper divisors (17964479).

211133221 is a wasteful number, since it uses less digits than its factorization.

211133221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2616 (or 2603 counting only the distinct ones).

The product of its digits is 72, while the sum is 16.

The square root of 211133221 is about 14530.4239786732. The cubic root of 211133221 is about 595.4594488164.

Adding to 211133221 its reverse (122331112), we get a palindrome (333464333).

The spelling of 211133221 in words is "two hundred eleven million, one hundred thirty-three thousand, two hundred twenty-one".