20212212221 has 12 divisors (see below), whose sum is σ = 20706088320. Its totient is φ = 19729863720.

The previous prime is 20212212211. The next prime is 20212212233. The reversal of 20212212221 is 12221221202.

It is a happy number.

It is not a de Polignac number, because 20212212221 - 2²² = 20208017917 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20212212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20212212211) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4788650 + ... + 4792868.

It is an arithmetic number, because the mean of its divisors is an integer number (1725507360).

Almost surely, 2^20212212221 is an apocalyptic number.

It is an amenable number.

20212212221 is a deficient number, since it is larger than the sum of its proper divisors (493876099).

20212212221 is an equidigital number, since it uses as much as digits as its factorization.

20212212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6896 (or 6853 counting only the distinct ones).

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

Adding to 20212212221 its reverse (12221221202), we get a palindrome (32433433423).

The spelling of 20212212221 in words is "twenty billion, two hundred twelve million, two hundred twelve thousand, two hundred twenty-one".