212213221 has 16 divisors (see below), whose sum is σ = 235037376. Its totient is φ = 190000000.

The previous prime is 212213189. The next prime is 212213231. The reversal of 212213221 is 122312212.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 212213221 - 2⁵ = 212213189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212213195 and 212213204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212213231) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 278481 + ... + 279241.

It is an arithmetic number, because the mean of its divisors is an integer number (14689836).

Almost surely, 2^212213221 is an apocalyptic number.

It is an amenable number.

212213221 is a deficient number, since it is larger than the sum of its proper divisors (22824155).

212213221 is a wasteful number, since it uses less digits than its factorization.

212213221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1124.

The product of its digits is 96, while the sum is 16.

The square root of 212213221 is about 14567.5399776352. The cubic root of 212213221 is about 596.4730312578.

Adding to 212213221 its reverse (122312212), we get a palindrome (334525433).

It can be divided in two parts, 21221 and 3221, that added together give a palindrome (24442).

The spelling of 212213221 in words is "two hundred twelve million, two hundred thirteen thousand, two hundred twenty-one".