1947391 has 2 divisors, whose sum is σ = 1947392. Its totient is φ = 1947390.

The previous prime is 1947383. The next prime is 1947397. The reversal of 1947391 is 1937491.

It is a strong prime.

It is an emirp because it is prime and its reverse (1937491) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1947391 - 2³ = 1947383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1947397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 973695 + 973696.

It is an arithmetic number, because the mean of its divisors is an integer number (973696).

2^1947391 is an apocalyptic number.

1947391 is a deficient number, since it is larger than the sum of its proper divisors (1).

1947391 is an equidigital number, since it uses as much as digits as its factorization.

1947391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6804, while the sum is 34.

The square root of 1947391 is about 1395.4895198460. The cubic root of 1947391 is about 124.8775547631.

The spelling of 1947391 in words is "one million, nine hundred forty-seven thousand, three hundred ninety-one".