22021121212221 has 4 divisors (see below), whose sum is σ = 29361494949632. Its totient is φ = 14680747474812.

The previous prime is 22021121212201. The next prime is 22021121212249. The reversal of 22021121212221 is 12221212112022.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 22021121212221 - 2⁶ = 22021121212157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021121212201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3670186868701 + ... + 3670186868706.

It is an arithmetic number, because the mean of its divisors is an integer number (7340373737408).

Almost surely, 2^{22021121212221} is an apocalyptic number.

It is an amenable number.

22021121212221 is a deficient number, since it is larger than the sum of its proper divisors (7340373737411).

22021121212221 is an equidigital number, since it uses as much as digits as its factorization.

22021121212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7340373737410.

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 22021121212221 its reverse (12221212112022), we get a palindrome (34242333324243).

The spelling of 22021121212221 in words is "twenty-two trillion, twenty-one billion, one hundred twenty-one million, two hundred twelve thousand, two hundred twenty-one".