1206391 has 2 divisors, whose sum is σ = 1206392. Its totient is φ = 1206390.

The previous prime is 1206383. The next prime is 1206407. The reversal of 1206391 is 1936021.

It is a weak prime.

It is an emirp because it is prime and its reverse (1936021) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1206391 - 2³ = 1206383 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 (1206341) 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 as a sum of consecutive naturals, namely, 603195 + 603196.

It is an arithmetic number, because the mean of its divisors is an integer number (603196).

2^1206391 is an apocalyptic number.

1206391 is a deficient number, since it is larger than the sum of its proper divisors (1).

1206391 is an equidigital number, since it uses as much as digits as its factorization.

1206391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 1206391 is about 1098.3583204037. The cubic root of 1206391 is about 106.4541744113.

The spelling of 1206391 in words is "one million, two hundred six thousand, three hundred ninety-one".