121911191 has 2 divisors, whose sum is σ = 121911192. Its totient is φ = 121911190.

The previous prime is 121911187. The next prime is 121911203. The reversal of 121911191 is 191119121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121911191 - 2² = 121911187 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121911191.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121911151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60955595 + 60955596.

It is an arithmetic number, because the mean of its divisors is an integer number (60955596).

Almost surely, 2^121911191 is an apocalyptic number.

121911191 is a deficient number, since it is larger than the sum of its proper divisors (1).

121911191 is an equidigital number, since it uses as much as digits as its factorization.

121911191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 162, while the sum is 26.

The square root of 121911191 is about 11041.3400907680. The cubic root of 121911191 is about 495.8471918605.

The spelling of 121911191 in words is "one hundred twenty-one million, nine hundred eleven thousand, one hundred ninety-one".