121121212100111 has 4 divisors (see below), whose sum is σ = 121121376280632. Its totient is φ = 121121047919592.

The previous prime is 121121212100051. The next prime is 121121212100173. The reversal of 121121212100111 is 111001212121121.

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 121121212100111 - 2⁶ = 121121212100047 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 121121212100111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121121212150111) 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, 80978645 + ... + 82460798.

It is an arithmetic number, because the mean of its divisors is an integer number (30280344070158).

Almost surely, 2^{121121212100111} is an apocalyptic number.

121121212100111 is a deficient number, since it is larger than the sum of its proper divisors (164180521).

121121212100111 is an equidigital number, since it uses as much as digits as its factorization.

121121212100111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164180520.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 121121212100111 its reverse (111001212121121), we get a palindrome (232122424221232).

The spelling of 121121212100111 in words is "one hundred twenty-one trillion, one hundred twenty-one billion, two hundred twelve million, one hundred thousand, one hundred eleven".