21021221220222 has 8 divisors (see below), whose sum is σ = 42042442440456. Its totient is φ = 7007073740072.

The previous prime is 21021221220119. The next prime is 21021221220283. The reversal of 21021221220222 is 22202212212012.

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

21021221220222 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1751768435013 + ... + 1751768435024.

It is an arithmetic number, because the mean of its divisors is an integer number (5255305305057).

Almost surely, 2^{21021221220222} is an apocalyptic number.

21021221220222 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21021221220222 is a wasteful number, since it uses less digits than its factorization.

21021221220222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3503536870042.

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 21021221220222 its reverse (22202212212012), we get a palindrome (43223433432234).

The spelling of 21021221220222 in words is "twenty-one trillion, twenty-one billion, two hundred twenty-one million, two hundred twenty thousand, two hundred twenty-two".