1122222121 has 4 divisors (see below), whose sum is σ = 1124814292. Its totient is φ = 1119629952.

The previous prime is 1122222119. The next prime is 1122222133. The reversal of 1122222121 is 1212222211.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1212222211 = 19 ⋅63801169.

It can be written as a sum of positive squares in 2 ways, for example, as 605160000 + 517062121 = 24600^2 + 22739^2 .

It is a cyclic number.

It is not a de Polignac number, because 1122222121 - 2¹ = 1122222119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1122222095 and 1122222104.

It is not an unprimeable number, because it can be changed into a prime (1122222151) 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, 1295436 + ... + 1296301.

It is an arithmetic number, because the mean of its divisors is an integer number (281203573).

Almost surely, 2^1122222121 is an apocalyptic number.

It is an amenable number.

1122222121 is a deficient number, since it is larger than the sum of its proper divisors (2592171).

1122222121 is an equidigital number, since it uses as much as digits as its factorization.

1122222121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2592170.

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

The square root of 1122222121 is about 33499.5838929381. The cubic root of 1122222121 is about 1039.1851732125.

Adding to 1122222121 its reverse (1212222211), we get a palindrome (2334444332).

The spelling of 1122222121 in words is "one billion, one hundred twenty-two million, two hundred twenty-two thousand, one hundred twenty-one".