212221224 has 24 divisors (see below), whose sum is σ = 574766010. Its totient is φ = 70740384.

The previous prime is 212221223. The next prime is 212221237. The reversal of 212221224 is 422122212.

It can be written as a sum of positive squares in only one way, i.e., 182736324 + 29484900 = 13518^2 + 5430^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 212221197 and 212221206.

It is not an unprimeable number, because it can be changed into a prime (212221223) 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 5 ways as a sum of consecutive naturals, for example, 1473687 + ... + 1473830.

Almost surely, 2^212221224 is an apocalyptic number.

212221224 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

212221224 is an abundant number, since it is smaller than the sum of its proper divisors (362544786).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212221224 is a wasteful number, since it uses less digits than its factorization.

212221224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2947529 (or 2947522 counting only the distinct ones).

The product of its digits is 256, while the sum is 18.

The square root of 212221224 is about 14567.8146610945. The cubic root of 212221224 is about 596.4805292413.

Adding to 212221224 its reverse (422122212), we get a palindrome (634343436).

The spelling of 212221224 in words is "two hundred twelve million, two hundred twenty-one thousand, two hundred twenty-four".