3111122221 has 2 divisors, whose sum is σ = 3111122222. Its totient is φ = 3111122220.

The previous prime is 3111122173. The next prime is 3111122237. The reversal of 3111122221 is 1222211113.

It is an a-pointer prime, because the next prime (3111122237) can be obtained adding 3111122221 to its sum of digits (16).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2276721225 + 834400996 = 47715^2 + 28886^2 .

It is a cyclic number.

It is not a de Polignac number, because 3111122221 - 2⁷ = 3111122093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 3111122195 and 3111122204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3111122921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1555561110 + 1555561111.

It is an arithmetic number, because the mean of its divisors is an integer number (1555561111).

Almost surely, 2^3111122221 is an apocalyptic number.

It is an amenable number.

3111122221 is a deficient number, since it is larger than the sum of its proper divisors (1).

3111122221 is an equidigital number, since it uses as much as digits as its factorization.

3111122221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48, while the sum is 16.

The square root of 3111122221 is about 55777.4346936106. The cubic root of 3111122221 is about 1459.8414510071.

Adding to 3111122221 its reverse (1222211113), we get a palindrome (4333333334).

The spelling of 3111122221 in words is "three billion, one hundred eleven million, one hundred twenty-two thousand, two hundred twenty-one".