11121211222121 has 48 divisors (see below), whose sum is σ = 15202838907648. Its totient is φ = 7997051462400.

The previous prime is 11121211222097. The next prime is 11121211222133. The reversal of 11121211222121 is 12122211212111.

It is a happy number.

It is not a de Polignac number, because 11121211222121 - 2¹⁸ = 11121210959977 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11121211222093 and 11121211222102.

It is not an unprimeable number, because it can be changed into a prime (11121211222421) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25223861 + ... + 25660973.

It is an arithmetic number, because the mean of its divisors is an integer number (316725810576).

Almost surely, 2^{11121211222121} is an apocalyptic number.

11121211222121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11121211222121 is a deficient number, since it is larger than the sum of its proper divisors (4081627685527).

11121211222121 is a wasteful number, since it uses less digits than its factorization.

11121211222121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440782 (or 440775 counting only the distinct ones).

The product of its digits is 64, while the sum is 20.

Adding to 11121211222121 its reverse (12122211212111), we get a palindrome (23243422434232).

The spelling of 11121211222121 in words is "eleven trillion, one hundred twenty-one billion, two hundred eleven million, two hundred twenty-two thousand, one hundred twenty-one".