3111222212221 has 4 divisors (see below), whose sum is σ = 3111704653500. Its totient is φ = 3110739770944.

The previous prime is 3111222212213. The next prime is 3111222212237. The reversal of 3111222212221 is 1222122221113.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2610198903321 + 501023308900 = 1615611^2 + 707830^2 .

It is a cyclic number.

It is not a de Polignac number, because 3111222212221 - 2³ = 3111222212213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3111222212192 and 3111222212201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3111222212201) 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, 241210966 + ... + 241223863.

It is an arithmetic number, because the mean of its divisors is an integer number (777926163375).

Almost surely, 2^{3111222212221} is an apocalyptic number.

It is an amenable number.

3111222212221 is a deficient number, since it is larger than the sum of its proper divisors (482441279).

3111222212221 is an equidigital number, since it uses as much as digits as its factorization.

3111222212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 482441278.

The product of its digits is 384, while the sum is 22.

Adding to 3111222212221 its reverse (1222122221113), we get a palindrome (4333344433334).

The spelling of 3111222212221 in words is "three trillion, one hundred eleven billion, two hundred twenty-two million, two hundred twelve thousand, two hundred twenty-one".