11111212011121 has 4 divisors (see below), whose sum is σ = 11127062528244. Its totient is φ = 11095361494000.

The previous prime is 11111212011103. The next prime is 11111212011143. The reversal of 11111212011121 is 12111021211111.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9371282175025 + 1739929836096 = 3061255^2 + 1319064^2 .

It is a cyclic number.

It is not a de Polignac number, because 11111212011121 - 2⁵ = 11111212011089 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11111212011095 and 11111212011104.

It is not an unprimeable number, because it can be changed into a prime (11111212071121) 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, 7925257510 + ... + 7925258911.

It is an arithmetic number, because the mean of its divisors is an integer number (2781765632061).

Almost surely, 2^{11111212011121} is an apocalyptic number.

It is an amenable number.

11111212011121 is a deficient number, since it is larger than the sum of its proper divisors (15850517123).

11111212011121 is an equidigital number, since it uses as much as digits as its factorization.

11111212011121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15850517122.

The product of its (nonzero) digits is 8, while the sum is 16.

Adding to 11111212011121 its reverse (12111021211111), we get a palindrome (23222233222232).

The spelling of 11111212011121 in words is "eleven trillion, one hundred eleven billion, two hundred twelve million, eleven thousand, one hundred twenty-one".