111211211122121 has 16 divisors (see below), whose sum is σ = 121689917870400. Its totient is φ = 100793947531200.

The previous prime is 111211211122013. The next prime is 111211211122139. The reversal of 111211211122121 is 121221112112111.

It is a de Polignac number, because none of the positive numbers 2^k-111211211122121 is a prime.

It is a super-2 number, since 2×111211211122121² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 111211211122093 and 111211211122102.

It is not an unprimeable number, because it can be changed into a prime (111211211122621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 246302915 + ... + 246754023.

It is an arithmetic number, because the mean of its divisors is an integer number (7605619866900).

Almost surely, 2^{111211211122121} is an apocalyptic number.

111211211122121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111211211122121 is a deficient number, since it is larger than the sum of its proper divisors (10478706748279).

111211211122121 is a wasteful number, since it uses less digits than its factorization.

111211211122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519160.

The product of its digits is 32, while the sum is 20.

Adding to 111211211122121 its reverse (121221112112111), we get a palindrome (232432323234232).

The spelling of 111211211122121 in words is "one hundred eleven trillion, two hundred eleven billion, two hundred eleven million, one hundred twenty-two thousand, one hundred twenty-one".