1212110222221 has 4 divisors (see below), whose sum is σ = 1212561326592. Its totient is φ = 1211659117852.

The previous prime is 1212110222203. The next prime is 1212110222233. The reversal of 1212110222221 is 1222220112121.

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 1212110222221 - 2³⁹ = 662354408333 is a prime.

It is a super-2 number, since 2×1212110222221² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212110222291) 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, 225548155 + ... + 225553528.

It is an arithmetic number, because the mean of its divisors is an integer number (303140331648).

Almost surely, 2^{1212110222221} is an apocalyptic number.

It is an amenable number.

1212110222221 is a deficient number, since it is larger than the sum of its proper divisors (451104371).

1212110222221 is an equidigital number, since it uses as much as digits as its factorization.

1212110222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451104370.

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

Adding to 1212110222221 its reverse (1222220112121), we get a palindrome (2434330334342).

The spelling of 1212110222221 in words is "one trillion, two hundred twelve billion, one hundred ten million, two hundred twenty-two thousand, two hundred twenty-one".