1209191 has 2 divisors, whose sum is σ = 1209192. Its totient is φ = 1209190.

The previous prime is 1209181. The next prime is 1209199. The reversal of 1209191 is 1919021.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1209191 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 (1209199) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 604595 + 604596.

It is an arithmetic number, because the mean of its divisors is an integer number (604596).

2^1209191 is an apocalyptic number.

1209191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1209191 is an equidigital number, since it uses as much as digits as its factorization.

1209191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 1209191 is about 1099.6322112416. The cubic root of 1209191 is about 106.5364698363.

The spelling of 1209191 in words is "one million, two hundred nine thousand, one hundred ninety-one".