121221320111 has 4 divisors (see below), whose sum is σ = 121431409632. Its totient is φ = 121011230592.

The previous prime is 121221320093. The next prime is 121221320123. The reversal of 121221320111 is 111023122121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 111023122121 = 12911 ⋅8599111.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121221320111 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 121221320111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221320131) 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, 105043895 + ... + 105045048.

It is an arithmetic number, because the mean of its divisors is an integer number (30357852408).

Almost surely, 2^121221320111 is an apocalyptic number.

121221320111 is a deficient number, since it is larger than the sum of its proper divisors (210089521).

121221320111 is an equidigital number, since it uses as much as digits as its factorization.

121221320111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210089520.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 121221320111 its reverse (111023122121), we get a palindrome (232244442232).

The spelling of 121221320111 in words is "one hundred twenty-one billion, two hundred twenty-one million, three hundred twenty thousand, one hundred eleven".