212202221 has 16 divisors (see below), whose sum is σ = 265545600. Its totient is φ = 164738880.

The previous prime is 212202191. The next prime is 212202229. The reversal of 212202221 is 122202212.

It is a cyclic number.

It is not a de Polignac number, because 212202221 - 2²⁶ = 145093357 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212202196 and 212202205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212202229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16355 + ... + 26303.

It is an arithmetic number, because the mean of its divisors is an integer number (16596600).

Almost surely, 2^212202221 is an apocalyptic number.

It is an amenable number.

212202221 is a deficient number, since it is larger than the sum of its proper divisors (53343379).

212202221 is a wasteful number, since it uses less digits than its factorization.

212202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10244.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 212202221 is about 14567.1624210071. The cubic root of 212202221 is about 596.4627250876.

Adding to 212202221 its reverse (122202212), we get a palindrome (334404433).

Subtracting from 212202221 its reverse (122202212), we obtain a palindrome (90000009).

The spelling of 212202221 in words is "two hundred twelve million, two hundred two thousand, two hundred twenty-one".