211212032221 has 4 divisors (see below), whose sum is σ = 216363545244. Its totient is φ = 206060519200.

The previous prime is 211212032219. The next prime is 211212032249. The reversal of 211212032221 is 122230212112.

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 81730804996 + 129481227225 = 285886^2 + 359835^2 .

It is a cyclic number.

It is not a de Polignac number, because 211212032221 - 2¹ = 211212032219 is a prime.

It is a super-2 number, since 2×211212032221² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211212632221) 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, 2575756450 + ... + 2575756531.

It is an arithmetic number, because the mean of its divisors is an integer number (54090886311).

Almost surely, 2^211212032221 is an apocalyptic number.

It is an amenable number.

211212032221 is a deficient number, since it is larger than the sum of its proper divisors (5151513023).

211212032221 is an equidigital number, since it uses as much as digits as its factorization.

211212032221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5151513022.

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

Adding to 211212032221 its reverse (122230212112), we get a palindrome (333442244333).

The spelling of 211212032221 in words is "two hundred eleven billion, two hundred twelve million, thirty-two thousand, two hundred twenty-one".