121111211210111 has 4 divisors (see below), whose sum is σ = 121454302460352. Its totient is φ = 120768119959872.

The previous prime is 121111211210107. The next prime is 121111211210131. The reversal of 121111211210111 is 111012112111121.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 121111211210111 - 2² = 121111211210107 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121111211210111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121111211210131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171545624591 + ... + 171545625296.

It is an arithmetic number, because the mean of its divisors is an integer number (30363575615088).

Almost surely, 2^{121111211210111} is an apocalyptic number.

121111211210111 is a deficient number, since it is larger than the sum of its proper divisors (343091250241).

121111211210111 is an equidigital number, since it uses as much as digits as its factorization.

121111211210111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343091250240.

The product of its (nonzero) digits is 8, while the sum is 17.

Adding to 121111211210111 its reverse (111012112111121), we get a palindrome (232123323321232).

The spelling of 121111211210111 in words is "one hundred twenty-one trillion, one hundred eleven billion, two hundred eleven million, two hundred ten thousand, one hundred eleven".