11101122121 has 4 divisors (see below), whose sum is σ = 11129660100. Its totient is φ = 11072584144.

The previous prime is 11101122119. The next prime is 11101122127. The reversal of 11101122121 is 12122110111.

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: 12122110111 = 11171 ⋅1085141.

It can be written as a sum of positive squares in 2 ways, for example, as 8201838096 + 2899284025 = 90564^2 + 53845^2 .

It is a cyclic number.

It is not a de Polignac number, because 11101122121 - 2¹ = 11101122119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11101122127) 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, 14268406 + ... + 14269183.

It is an arithmetic number, because the mean of its divisors is an integer number (2782415025).

Almost surely, 2^11101122121 is an apocalyptic number.

It is an amenable number.

11101122121 is a deficient number, since it is larger than the sum of its proper divisors (28537979).

11101122121 is an equidigital number, since it uses as much as digits as its factorization.

11101122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28537978.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 11101122121 its reverse (12122110111), we get a palindrome (23223232232).

The spelling of 11101122121 in words is "eleven billion, one hundred one million, one hundred twenty-two thousand, one hundred twenty-one".