221021212210 has 8 divisors (see below), whose sum is σ = 397838181996. Its totient is φ = 88408484880.

The previous prime is 221021212171. The next prime is 221021212211. The reversal of 221021212210 is 12212120122.

It is a happy number.

221021212210 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 198847321929 + 22173890281 = 445923^2 + 148909^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (221021212211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11051060601 + ... + 11051060620.

Almost surely, 2^221021212210 is an apocalyptic number.

221021212210 is a deficient number, since it is larger than the sum of its proper divisors (176816969786).

221021212210 is a wasteful number, since it uses less digits than its factorization.

221021212210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22102121228.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221021212210 its reverse (12212120122), we get a palindrome (233233332332).

The spelling of 221021212210 in words is "two hundred twenty-one billion, twenty-one million, two hundred twelve thousand, two hundred ten".