1591871 has 2 divisors, whose sum is σ = 1591872. Its totient is φ = 1591870.

The previous prime is 1591859. The next prime is 1591873. The reversal of 1591871 is 1781951.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1591871 is a prime.

Together with 1591873, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1591873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 795935 + 795936.

It is an arithmetic number, because the mean of its divisors is an integer number (795936).

2^1591871 is an apocalyptic number.

1591871 is a deficient number, since it is larger than the sum of its proper divisors (1).

1591871 is an equidigital number, since it uses as much as digits as its factorization.

1591871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2520, while the sum is 32.

The square root of 1591871 is about 1261.6937029248. The cubic root of 1591871 is about 116.7622952904.

The spelling of 1591871 in words is "one million, five hundred ninety-one thousand, eight hundred seventy-one".