11122212121 has 4 divisors (see below), whose sum is σ = 11148757200. Its totient is φ = 11095667044.

The previous prime is 11122212119. The next prime is 11122212139. The reversal of 11122212121 is 12121222111.

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 11122212121 - 2¹ = 11122212119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11122212095 and 11122212104.

It is not an unprimeable number, because it can be changed into a prime (11122212151) 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, 13271911 + ... + 13272748.

It is an arithmetic number, because the mean of its divisors is an integer number (2787189300).

Almost surely, 2^11122212121 is an apocalyptic number.

It is an amenable number.

11122212121 is a deficient number, since it is larger than the sum of its proper divisors (26545079).

11122212121 is an equidigital number, since it uses as much as digits as its factorization.

11122212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26545078.

The product of its digits is 32, while the sum is 16.

Adding to 11122212121 its reverse (12121222111), we get a palindrome (23243434232).

The spelling of 11122212121 in words is "eleven billion, one hundred twenty-two million, two hundred twelve thousand, one hundred twenty-one".