121911 has 4 divisors (see below), whose sum is σ = 162552. Its totient is φ = 81272.

The previous prime is 121909. The next prime is 121921. The reversal of 121911 is 119121.

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 121911 - 2¹ = 121909 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20316 + ... + 20321.

It is an arithmetic number, because the mean of its divisors is an integer number (40638).

2¹²¹⁹¹¹ is an apocalyptic number.

121911 is a deficient number, since it is larger than the sum of its proper divisors (40641).

121911 is an equidigital number, since it uses as much as digits as its factorization.

121911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40640.

The product of its digits is 18, while the sum is 15.

The square root of 121911 is about 349.1575575582. The cubic root of 121911 is about 49.5846932910.

It can be divided in two parts, 1 and 21911, that added together give a palindrome (21912).

The spelling of 121911 in words is "one hundred twenty-one thousand, nine hundred eleven".