221212330 has 16 divisors (see below), whose sum is σ = 421605000. Its totient is φ = 83279872.

The previous prime is 221212309. The next prime is 221212333. The reversal of 221212330 is 33212122.

It can be written as a sum of positive squares in 4 ways, for example, as 131171209 + 90041121 = 11453^2 + 9489^2 .

It is not an unprimeable number, because it can be changed into a prime (221212333) 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 7 ways as a sum of consecutive naturals, for example, 650455 + ... + 650794.

Almost surely, 2^221212330 is an apocalyptic number.

221212330 is a deficient number, since it is larger than the sum of its proper divisors (200392670).

221212330 is a wasteful number, since it uses less digits than its factorization.

221212330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1301273.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 221212330 is about 14873.2084635428. The cubic root of 221212330 is about 604.7879228439.

Adding to 221212330 its reverse (33212122), we get a palindrome (254424452).

The spelling of 221212330 in words is "two hundred twenty-one million, two hundred twelve thousand, three hundred thirty".