21221012222 has 8 divisors (see below), whose sum is σ = 31832139000. Its totient is φ = 10610299224.

The previous prime is 21221012213. The next prime is 21221012251. The reversal of 21221012222 is 22221012212.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21221012222.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131429 + ... + 244367.

It is an arithmetic number, because the mean of its divisors is an integer number (3979017375).

Almost surely, 2^21221012222 is an apocalyptic number.

21221012222 is a deficient number, since it is larger than the sum of its proper divisors (10611126778).

21221012222 is a wasteful number, since it uses less digits than its factorization.

21221012222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206890.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21221012222 its reverse (22221012212), we get a palindrome (43442024434).

The spelling of 21221012222 in words is "twenty-one billion, two hundred twenty-one million, twelve thousand, two hundred twenty-two".