111212312121 has 48 divisors (see below), whose sum is σ = 176657820480. Its totient is φ = 69127603200.

The previous prime is 111212312063. The next prime is 111212312131. The reversal of 111212312121 is 121213212111.

It is a happy number.

It is not a de Polignac number, because 111212312121 - 2⁷ = 111212311993 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111212312094 and 111212312103.

It is not an unprimeable number, because it can be changed into a prime (111212312131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 768321 + ... + 901521.

It is an arithmetic number, because the mean of its divisors is an integer number (3680371260).

Almost surely, 2^111212312121 is an apocalyptic number.

It is an amenable number.

111212312121 is a deficient number, since it is larger than the sum of its proper divisors (65445508359).

111212312121 is a wasteful number, since it uses less digits than its factorization.

111212312121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133351 (or 133328 counting only the distinct ones).

The product of its digits is 48, while the sum is 18.

Adding to 111212312121 its reverse (121213212111), we get a palindrome (232425524232).

The spelling of 111212312121 in words is "one hundred eleven billion, two hundred twelve million, three hundred twelve thousand, one hundred twenty-one".