212201221221 has 36 divisors (see below), whose sum is σ = 337121491980. Its totient is φ = 128526393600.

The previous prime is 212201221163. The next prime is 212201221223. The reversal of 212201221221 is 122122102212.

It is a happy number.

212201221221 is a `hidden beast` number, since 2 + 1 + 220 + 1 + 221 + 221 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 77904624996 + 134296596225 = 279114^2 + 366465^2 .

It is not a de Polignac number, because 212201221221 - 2⁹ = 212201220709 is a prime.

It is a super-3 number, since 3×212201221221³ (a number of 35 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 212201221194 and 212201221203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212201221223) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1705165 + ... + 1825373.

Almost surely, 2^212201221221 is an apocalyptic number.

It is an amenable number.

212201221221 is a deficient number, since it is larger than the sum of its proper divisors (124920270759).

212201221221 is a wasteful number, since it uses less digits than its factorization.

212201221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121858 (or 121844 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 212201221221 its reverse (122122102212), we get a palindrome (334323323433).

The spelling of 212201221221 in words is "two hundred twelve billion, two hundred one million, two hundred twenty-one thousand, two hundred twenty-one".