1122212221 has 8 divisors (see below), whose sum is σ = 1215689720. Its totient is φ = 1035886176.

The previous prime is 1122212213. The next prime is 1122212239. The reversal of 1122212221 is 1222122211.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 405579321 + 716632900 = 20139^2 + 26770^2 .

It is not a de Polignac number, because 1122212221 - 2³ = 1122212213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1122212195 and 1122212204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1122212291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 253200 + ... + 257593.

It is an arithmetic number, because the mean of its divisors is an integer number (151961215).

Almost surely, 2^1122212221 is an apocalyptic number.

It is an amenable number.

1122212221 is a deficient number, since it is larger than the sum of its proper divisors (93477499).

1122212221 is an frugal number, since it uses more digits than its factorization.

1122212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 510832 (or 510806 counting only the distinct ones).

The product of its digits is 64, while the sum is 16.

The square root of 1122212221 is about 33499.4361295828. The cubic root of 1122212221 is about 1039.1821173815.

Adding to 1122212221 its reverse (1222122211), we get a palindrome (2344334432).

The spelling of 1122212221 in words is "one billion, one hundred twenty-two million, two hundred twelve thousand, two hundred twenty-one".