111201212121 has 4 divisors (see below), whose sum is σ = 148268282832. Its totient is φ = 74134141412.

The previous prime is 111201212047. The next prime is 111201212123. The reversal of 111201212121 is 121212102111.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 111201212121 - 2⁹ = 111201211609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 111201212121.

It is not an unprimeable number, because it can be changed into a prime (111201212123) 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, 18533535351 + ... + 18533535356.

It is an arithmetic number, because the mean of its divisors is an integer number (37067070708).

Almost surely, 2^111201212121 is an apocalyptic number.

It is an amenable number.

111201212121 is a deficient number, since it is larger than the sum of its proper divisors (37067070711).

111201212121 is an equidigital number, since it uses as much as digits as its factorization.

111201212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37067070710.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 111201212121 its reverse (121212102111), we get a palindrome (232413314232).

The spelling of 111201212121 in words is "one hundred eleven billion, two hundred one million, two hundred twelve thousand, one hundred twenty-one".