2221212011221 has 4 divisors (see below), whose sum is σ = 2538528012832. Its totient is φ = 1903896009612.

The previous prime is 2221212011219. The next prime is 2221212011237. The reversal of 2221212011221 is 1221102121222.

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 a cyclic number.

It is not a de Polignac number, because 2221212011221 - 2¹ = 2221212011219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2221212011201) 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, 158658000795 + ... + 158658000808.

It is an arithmetic number, because the mean of its divisors is an integer number (634632003208).

Almost surely, 2^{2221212011221} is an apocalyptic number.

It is an amenable number.

2221212011221 is a deficient number, since it is larger than the sum of its proper divisors (317316001611).

2221212011221 is an equidigital number, since it uses as much as digits as its factorization.

2221212011221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317316001610.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 2221212011221 its reverse (1221102121222), we get a palindrome (3442314132443).

The spelling of 2221212011221 in words is "two trillion, two hundred twenty-one billion, two hundred twelve million, eleven thousand, two hundred twenty-one".