121409191 has 2 divisors, whose sum is σ = 121409192. Its totient is φ = 121409190.

The previous prime is 121409047. The next prime is 121409209. The reversal of 121409191 is 191904121.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121409191 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121406191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60704595 + 60704596.

It is an arithmetic number, because the mean of its divisors is an integer number (60704596).

Almost surely, 2^121409191 is an apocalyptic number.

121409191 is a deficient number, since it is larger than the sum of its proper divisors (1).

121409191 is an equidigital number, since it uses as much as digits as its factorization.

121409191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 28.

The square root of 121409191 is about 11018.5838926788. The cubic root of 121409191 is about 495.1656636948.

The spelling of 121409191 in words is "one hundred twenty-one million, four hundred nine thousand, one hundred ninety-one".